An inmate was beaten to death Thursday evening in the maximum security wing of Cook County Jail, officials said.

About 5:10 p.m. Thursday, correctional staff at the jail found Marvell Reasonover, 28, unresponsive in his cell and “immediately began life-saving measures,” the Cook County sheriff’s office said in a statement.

Reasonover was taken to Mount Sinai Hospital, where he was pronounced dead, officials said. His death was caused by multiple injuries from an assault and was ruled a homicide, according to the Cook County medical examiner’s office.

His cellmate was “secured and escorted out of the cell,” officials said.

Reasonover was in custody for having a weapon as a felon in August 2020 when Chicago police officers found a loaded weapon in a vehicle he was in, the sheriff’s office said. He admitted to officers that the weapon was his.

In December that year, he also allegedly stole a Jeep at gunpoint after arranging online to meet with the owner, who was advertising the Jeep, officials said.

While in custody, Reasonover was charged with aggravated battery to a peace officer, public indecency and criminal damage to property.