BASTROP, Texas (KXAN) — The Bastrop County Sheriff’s Office said a jawbone that was found on a sand bar in the Colorado River in July belongs to a Houston man who was reported missing in 2015. The man’s family questioned in a statement whether law enforcement did everything they could to help their son.

The sheriff’s office held a press conference Friday with the Bastrop Police Department and revealed the jaw bone belonged to Johnathan Lee Hamilton. 

“The Bastrop Police Department extends its heartfelt sorrow for the Hamilton family as they learned today that the jaw bone that was recovered in the latter part of July adjacent to the Colorado River as being the remains of their missing son,” said Chief James Altgelt, Director of Public Safety and Chief of Police for the department.

Hamilton’s family thanked those who helped keep the search for him top of mind.

“He would have been 31 this year,” the Hamilton family wrote. “He never had a chance to fall in love, get married, or have children or to watch his little Sister grow up into such a beautiful woman. He was taken too soon us (sic).”

Law enforcement agencies worked together with The University of North Texas’ Center for Human Remains to identify who the bone belonged to, but many questions still remain.

Sheriff Maurice Cook said the 26-year-old Hamilton was reported missing by family in Houston back in 2015, which was discovered by the Bastrop Police Department when they responded to a suspicious person call at the Burleson Crossing Shopping Center on May 4, 2015.

Hamilton’s car had reportedly broken down in the parking lot of the shopping center and the vehicle had been there a while.

“We made contact with him, found that he was not suffering from a mental health crisis, that he was not a danger to himself or others and that he was in control of his mental faculties,” Chief Altgelt said at the news conference. “He chose to go on about his business and he was allowed to do so, which was appropriate.”

After that encounter with police, Algelt said Hamilton was removed as being missing/endangered. His parents traveled to Bastrop to look for Hamilton, but Altgelt said when they couldn’t find him, they requested he be re-entered into their system as missing and endangered on May 6, 2015 because he was diabetic and did not have his medication.

“We knew in our heart that our boy did not run away as some said,” the family’s statement said. “He needed help and the fire department who saw him that night, stated in writing that he needed help. Everyone there let him walk away.”

After more than 1,000 hours of searching for Hamilton and having their investigation reviewed by two outside agencies to be sure they hadn’t missed anything, Chief Altgelt said they had not been able to find him.

When the jaw bone turned up on July 29 and was later identified, the sheriff’s office launched an investigation into how he may have died.

But it’s still unclear how the bone got to the sand bar.

After an extensive search of the area along with Texas Search and Rescue teams and diver dogs, Cook said no other remains were found in the area.

“If this bone had been in the Colorado River, since 2015 that would be somewhat unusual, so we don’t know how the bone got there if it traveled into the river because of all the flooding we’ve had, we just don’t know,” Cook said.

The sheriff’s office and police department do hope that with the identification of the jaw bone that more leads will come in about what happened to Johnathan Hamilton and maybe help them find the rest of his remains.

Investigators have not ruled out foul play.

“We are still in the place we were 4 years ago,” his family said. “We don’t know what happened to Johnathan. Will we have closure? We are not sure. Time will tell. Was he murdered, was he in diabetic shock, was in pain and alone? That will haunt us.”