A 39-year-old inmate died at a detention center in Alexandria, Virginia, early Monday morning after law enforcement said he appeared to have suffered from a medical emergency.

Ahntais Lucas, 39, of Fairfax County was found alone in his cell at the William G. Truesdale Adult Detention Center, at around 4 a.m. He was suffering an “apparent medical emergency,” according to a news release from the sheriff’s office — which is investigating the death alongside police.

The jail’s staff worked to try to save Lucas’ life alongside medics with the Alexandria Fire Department who were called to the jail, deputies said. But Lucas was pronounced dead just before 4:45 a.m.

He had been in custody since Aug. 20, 2023, deputies said.

Police are conducting a death investigation and deputies will review what happened to make sure policies and procedures were followed, according to the news release.