INDIANAPOLIS (AP): A Marion County Jail inmate found unresponsive in his cell has died and authorities say an investigation into the cause is underway.

The Marion County Sheriff’s Office tells WRTV-TV that 35-year-old Walter Gamble was pronounced dead Saturday, shortly before 4:30 p.m.

Authorities say Gamble was jailed May 12 on criminal charges including deviate conduct, sexual misconduct with a minor and sexual battery.

Gamble was a registered sex offender. He was convicted in July 2013 of sexual misconduct with a minor and sexual battery.