'The terrorists don't know what they took': Dad of Washington D.C. boy, 11, who was killed in Sri Lanka attack mourns his 'brilliant' son who dreamed of being a neuroscientist as death toll climbs to 310

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The father of an 11-year-old boy who was killed in a Sri Lanka hotel that was targeted by a suicide bomber on Easter morning said the attacker robbed the world of a great mind.

'I don't know what is in the mind of a terrorist, but I'm sure they do not know what they took, they do not know what they took from the world,' Alexander Arrow said of his son, Kieran Shafritz de Zoysa. 

'They took a great mind who was going to be a neuroscientist and work on Alzheimer's diseases.'  

Arrow, a business executive from San Diego, told KTNV-TV that he last heard from his son, who was staying at the Cinnamon Grand Colombo, less than an hour before he was killed by a suicide bomber while in line for breakfast.

'He texted me back "can't talk right now" because he was in the elevator going to breakfast,' Arrow said. 

'It was about an hour after that when my phone started ringing.' 

Kieran Shafritz de Zoysa (left and right), was one the American victims identified on Monday as casualties of a suicide bombing in a Sri Lanka hotel

'They took a great mind who was going to be a neuroscientist and work on Alzheimer's diseases,' Alexander Arrow, Kieran's father, said

Arrow said Kieran's mother, who survived the attack, was calling him to inform him about the bombing. 

He said he was told by doctors that his son was killed instantly by the suicide bomber.

Arrow is the CEO of a California biomedical firm

'The terrorists didn't know what they were killing, but we should know what the world lost,' Arrow said. 

Arrow, who is the CEO at California biomedical firm Zelegent, said he had last seen his son when he came to visit his father for spring break in San Diego.

'He wanted to go kayaking,' the grieving father said. 

'In fact, his mom told me on the plane ride back to Sri Lanka last week he said he wanted to come back and do more kayaking. 

'You know it is a good time for some father talks. We had some deep talks out there.'

Arrow said his son was finishing up a semester in Sri Lanka before returning to the prestigious Sidwell Friends school in Washington, DC, where he was hoping to enroll in seventh grade this fall.

'He was learning Chinese and Sinhalese and Mandarin,' Arrow told ABC News. 

'He was into karate, which he took to. He wasn’t much for soccer or softball, but he loved karate. He played the trumpet and all the games. 

'He had a month or two to finish in Sri Lanka and was going to come back for the summer in July and start 7th grade in DC.' 

In a separate interview, he told ABC: 'Now he'll never be a teenager. He was going to make a major contribution to this world.'  

Arrow said the boy's mother Dhulsini 'devoted her life to him' and took great pains to expand his horizons.

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Kieran, a fifth grader who attended the prestigious Sidwell Friends school in Washington DC, (pictured with his mother Dhulsini) was among those killed in the terror attacks in Sri Lanka on Sunday 

'Her next thing was the Galapagos,' the dad said. 

'That was the next thing she had planned for him. 

'Both she and I have had only him as our only child so he can [have] the kind of devotion. 

'She devoted her life to him...She sacrificed all of her time to be with him everywhere. 

'To give him the culture of all of these places.'  

Sidwell, the $42,000-a-year school, which is a favorite among political families and is where Sasha Obama attends classes, announced his death in an email to parents. 

'Passionate about learning, he adored his friends, and was incredibly excited about returning to Sidwell Friends in the coming school year,' school principal Mamadou Guèye wrote in the email that was obtained by CNN. 

It remains unclear if anyone else in his family was harmed. He had been in Sri Lanka with his mother, who is from there, for an extended stay but was due to return to Sidwell next year.  

Arrow said he was told that the suicide bomber who struck the Cinnamon Grand Hotel in Colombo on Sunday instantly killed his son. Security forces are seen outside of the hotel after the bombing on Sunday

'As you know, Kieran Shafritz de Zoysa has been on a leave of absence from Sidwell Friends School, living and studying in Sri Lanka. We learned today that he died in the bombings in Sri Lanka on Easter,' the school's principal said in his email.

'This is obviously an unexpected tragedy for his family and for his greater community, including Sidwell Friends and the class of 2026. 

'Kieran was passionate about learning, he adored his friends, and he was incredibly excited about returning to Sidwell Friends this coming school year. 

'We are beyond sorry not to get the opportunity to welcome Kieran to the Middle School.' 

Dieter Kowalski, 40, had not been heard from since he landed in Sri Lanka early Sunday morning. He was in the country for work.  

On Monday morning, his brother confirmed that he was among those killed by a suicide bomber at the Cinnamon Grand Colombo hotel. 

A worker from the Cinnamon Grand Colombo Hotel told DailyMail.com on Monday that Kowalski was one of three Americans staying there. The other two were hospitalized in an unknown condition. 

One was Chimai Tran Luu. She was discharged from hospital afterwards.  

Kieran had been in Sri Lanka with his mother for an extended leave of absence from Sidwell. He was due to return to the Washington DC school for middle school but was studying in Sri Lanka, where he has family. Kieran is pictured left with his mother. His father is pictured right.

Two people with dual US-UK citizenship were killed in the explosions but it is unclear if Kowalski was among them. 

Secretary of State Mike Pompeo said on Sunday that 'several' US citizens were among the victims but the State Department has not given out any additional information.  

Dieter Kowalski, 40, from Denver, Colorado, was also killed 

Kowalski landed safely on the island and checked in to the Cinnamon Grand Colombo hotel at 3.45am on Sunday. 

The hotel was hit by a bomb five hours later, one of eight explosions that left more than 300 people dead. The other attacks targeted churches and hotels.

In a Facebook post on Monday, his grieving brother confirmed his death. 

'It is with great sadness and deep regret that as Dieter's brother that I confirm that Dieter was among the victims that passed away in Sri Lanka. 

'As we know that Dieter saw his friends as family, we would like to share our grief over this tragic incident. More information to follow. We have all lost a brother today... RIP Dieter,' he said.

Kowalski’s friends and family had tried to get information about him from the hotel and the Consulate General of Sri Lanka.  

He worked for an education technology company. He wrote on his Facebook page that he was traveling to Sri Lanka on business.

Kowalski posted a message on Facebook announcing his trip to Sri Lanka on Friday 

A manager at the Cinnamon Grand hotel in Colombo said the attacker had set off the horrific explosion in a packed restaurant at 8.30am, after waiting in a queue for a breakfast buffet.

Describing the Cinnamon Grand bombing, a hotel manager said the attacker had registered the night before as Mohamed Azzam Mohamed. 

The bomber was just about to be served when he set off the explosives which were strapped to his back, killing himself and numerous guests.  

The manager said: 'There was utter chaos. 

'It was 8.30am and it was busy. It was families.

'He came up to the top of the queue and set off the blast. 

'One of our managers who was welcoming guests was among those killed instantly.'

At least 35 foreigners are feared to have been killed in the attacks - including five Britons, two of whom were joint US-UK citizens. 

Two Canadian families are also reeling from the news of their loved ones' deaths.

Dilina Fernando, 17, of Calgary said he was informed on Sunday that two of his male cousins and one of their wives were killed in the attacks, according to the Canadian Broadcasting Corporation.

M. Lahiru and Sudhiva Fernando, and Lahiru's wife, M. Diliniee, were among those killed.

Sri Lankan security forces are shown near St Anthony's Shrine in Colombo on Monday, April 22 

A crime scene official inspects the site of a bomb blast inside a church in Negombo, Sri Lanka, which lost half its roof tiles with the force of the blast

Pictured are footwear and personal belongings of victims from the St. Sebastian Church after the attack on Monday 

Dimitra Silva, fourth left, weeps at a funeral for his 13-year-old brother Anos and his grandparents who were all killed together 

'We're just kind of shaken up... We hope that the numbers don't continue to rise, because every minute they're saying that the death toll is getting higher and higher. It's just hard to hear,' Fernando said.

'It's indescribable.' 

Fernando said his family lived about five minutes from where one of the eight bombings took place.

He said the family was fasting for two days in preparation to observe the Easter holiday.

'Sunday is the day that we celebrate,' Fernando said. 

'It's the day that we're back on our feet and we celebrate, we have a big mass. For something like that to happen on today of all days, it just hurts that much more.'

Samith Warnakulasuriya, of Edmonton, said a number of his cousins were also killed.

He said he received a call from his mother, who lives in Sri Lanka. She was safe, but the sound of ambulances was heard during the phone call.

'I was really devastated. I didn't know what to do. I stopped driving. I was breathless,' he said.

'I came home and I was shivering... My family members, nobody would have been thinking about any kind of explosion in the churches, where people pray to God. We are there for peace, for security.'  

Blood stains are seen on the wall and on a Jesus Christ statue at the St. Sebastian's Church after blast in Negombo, north of Colombo, Sri Lanka,after the bombing

Many of the statues inside the church remain in place, marked with the bomb blast or with blood, as investigators pick through the rubble

The benches and pews were scattered or reduced to splinters by the blast, one of eight which killed 310 people on Easter Sunday

Sri Lankan security personnel walk next to dead bodies on the floor amid blast debris at St. Anthony's Shrine following an explosion in the church in Kochchikade in Colombo on Sunday

Foreign Secretary Jeremy Hunt condemned the the 'horrifying attacks' which he said had killed 'several British nationals'.

Further fatalities are said to include three Indians, two Turks, one Portuguese citizen and an unknown number of Dutch and Chinese nationals.  

A bomb was found and safely destroyed at Sri Lanka's main airport on Sunday evening just hours after coordinated attacks killed 310 people in explosions at churches and five-star hotels on Easter Sunday. 

Eight blasts ripped through landmarks around the capital Colombo, and on Sri Lanka's east coast, targeting Christians, hotel guests and foreign tourists. 

More than 450 people were wounded and five British citizens were among the dead.

A a six-foot pipe bomb was later found by air force personal on a routine patrol at the country's main airport Bandaranaike International, also known as Katunayake Airport or Colombo International.  

A woman injured during one of the explosions to rip through Sri Lankan churches on Easter Sunday was taken to hospital in Batticaloa, Sri Lanka

Hospital staff push a trolley with a casualty after an explosion at a church in Batticaloa, Sri Lanka

Sri Lankan military stand guard near the explosion site at a church in Batticaloa,with police tape keeping out bystanders

'A PVC pipe which was six feet in length containing explosives in it was discovered,' Air Force Spokesman Gihan Seneviratne told the Sri Lankan Sunday Times.

He said the bomb device was discovered by Air Force personnel on a routine patrol and was disposed by the Explosives Ordinance Disposal Unit of the Air Force in a controlled area. 

The airport was put 'on lockdown' while the security forces examined and detonated the device, according to reports from the scene.  

It comes after six bombs went off in quick succession before another two blasts two hours later in Sri Lanka's worst violence since the end of its decades-long civil war in 2009. 

As details of the horror emerged today, Sri Lankan TV chef Shantha Mayadunne and her London-based daughter Nisanga were among the first victims named. 

The country's police chief had warned of an Islamic extremist plot to target 'prominent churches' just 10 days earlier, but no group has yet claimed responsibility for the attack.   

Sri Lanka's defense ministry has now ordered curfew with immediate effect 'until further notice' while access to social media messaging services has been shut down.  

More than 400 people have been injured after the initial six near-simultaneous explosions across the country, an official said (pictured: The aftermath in one of the churches)

Security forces inspect the scene after a blast targeting Shangri La hotel in Colombo, Sri Lanka on Easter Sunday

State minister of defence Ruwan Wijewardene said investigators have identified the culprits behind the 'terrorist' attacks (pictured: Shangri La hotel, Colombo)

At least 310 people are dead in an Easter Sunday terrorist attack targeting Christians in Sri Lanka after explosions ripped through high-end hotels and churches (pictured: Outside a hospital in Colombo) 

A map showing where the eight blasts went off today, six of them in very quick succession on Easter Sunday morning  

Last photo: Shantha Mayadunne (second left) and her daughter Nisanga (right) were among the victims of the Sri Lanka bomb attacks on Sunday. The family posted this picture of their Easter breakfast at the Shangri-La hotel just before the blast there

The bombings targeted the luxury Cinnamon Grand, Shangri-La and Kingsbury hotels as well as St Anthony's Shrine in Colombo, all frequented by tourists.  

Other blasts were reported at St. Sebastian's Church in Negombo, a majority-Catholic town, and at Zion Church in the eastern town of Batticalo.

Pictured: Shantha Mayadunne and her daughter Nisanga. The victims include at least 35 foreigners, believed to include Britons and Americans as well as nationals of Turkey, China, Portugal and the Netherlands

Later in the afternoon, two died in a strike at a hotel near a zoo in the south of Colombo, before a suspected suicide bomber killed police officers in the suburb of Orugodawatta in the north of the capital. 

Shantha Mayadunne and her daughter Nisanga, believed to have been a student in London, died just moments after sharing a picture of their Easter breakfast at the Shangri-La hotel. 

A friend of the family told Gulf News: 'Nisanga was a very popular girl in college. 

'Besides the fact that she was bright and smart, her mother Shantha Mayadume, a renowned chef, made her more popular in college. She was well respected and an inspirational chef for Sri Lankans.'  

Millions of tourists visit Sri Lanka every year but political crisis and religious tension have placed the industry under threat in recent months. 

No nation, organization or group has yet claimed responsibility for the outrage.

Ten days ago, according to documents seen by the AFP new agency, Sri Lanka's police chief Pujuth Jayasundara issued an intelligence alert to top officers warning Islamist suicide bombers planned to hit 'prominent churches'.

'A foreign intelligence agency has reported that the NTJ (National Thowheeth Jama'ath) is planning to carry out suicide attacks targeting prominent churches as well as the Indian high commission in Colombo,' the alert said.

The NTJ is a small radical Muslim group in Sri Lanka which has no history of mass fatal attacks, but came to prominence last year linked to the vandalism and desecration of Buddhist statues.

Povlsen, 46, and Anne Storm Pedersen, pictured together left, met when Anne began working in sales for Bestseller. Brit Alex Nicholson, 11, was killed with his mother Anita, 42, pictured together right, as they ate breakfast in the Shangri La in Colombo

Just days before the devastating attacks, one of Povlsen's children, Alma, shared a snap of her three siblings Astrid, Agnes and Alfred, next to a pool. It is not yet known which of Povlsen's three children have died