Maine State Police are investigating the death of an inmate at the York County Jail, according to Sheriff Bill King.Kimberly Pierce, 35, of Waterboro, died early Monday morning, King said.Pierce was sentenced on Monday to serve a 60-day sentence for two OUI convictions, driving to endanger, operating beyond license restrictions and violating conditions of release, King said.Officials said Pierce was admitted to the jail at 5:30 p.m. Monday and was found unresponsive just after 5 a.m. Tuesday.King said paramedics were called and she was declared dead.King said Pierce was not considered a suicide risk and was being held in a cell in the intake area at the time of her death. King said there is a lot of activity in that area.King said his office is reviewing all records and video regarding checks on her.