ST. LOUIS — The Force Investigations Unit (FIU) is investigating after a male detainee in the St. Louis City Justice Center died.

The detainee was taken to St. Louis University Hospital on Saturday, March 22, for a medical emergency. A toxicology report revealed no drugs in his system, but said seizures may be a contributing factor to his medical emergency. He was then transported back to the St. Louis City Justice Center after being evaluated by hospital staff.

However, he was found unresponsive in his cell around 9:30 a.m. the next morning. He was transported to Barnes-Jewish Hospital for treatment but was pronounced dead.

The St. Louis Metropolitan Police Department said there are no signs of trauma.

The FIU said it will conduct an "extensive investigation and report."

Further details have not been released.