The man who died in custody at the Northern Branch Jail Monday was identified as a 57-year-old Santa Maria resident, according to the Santa Barbara County Sheriff’s Office.

Investigators believe that the man — identified as David Lee Ligon — likely died of a drug overdose, said Raquel Zick, sheriff’s public information officer.

At about 2:19 p.m. on Monday, a custody deputy and a WellPath medical staff member were conducting medical procedures at the jail when they found Ligon, who did not respond to the check-in procedures, Zick said previously.

They entered Ligon’s cell to check on his condition, and found him to be unresponsive and not breathing.

“Custody deputies and WellPath medical staff began life-saving measures, including administering two rounds of Narcan, performing CPR, and placement of an automated external defibrillator (AED),” Zick said.

Despite those efforts, and those of county firefighters and AMR paramedics, Ligon was pronounced dead, Zick said.

Ligon had been booked into the jail on May 27, two days earlier, on suspicion of possession of narcotics for sale and transportation of a controlled substance, both felonies, and possession of narcotics and possession of paraphernalia, both misdemeanors, Zick said.

He was being held in custody in lieu of $30,000 bail.

“An initial investigation indicates this is a probable overdose-related death,” Zick said. “However, final cause and manner of death are pending.”