ORANGE — A walk-on football coach who sparked a 10-hour standoff with police at El Modena High School in Orange is facing additional charges for allegedly engaging in a sexual relationship with a minor student, authorities said Wednesday, May 3.

Michael James Snitzler, a 26-year-old assistant varsity football coach from Santa Ana, locked himself inside of a classroom with a loaded firearm and threatened suicide in a 10-hour standoff with police that began at about 11 a.m. on April 23, authorities said. Students and adults on campus were evacuated.

Snitzler eventually surrendered and was booked on suspicion of possession of a firearm and ammunition on a school campus.

He is now facing additional charges for engaging in a sexual relationship with a student from the school who is a minor, the Orange County District Attorney’s Office said Wednesday.

Prosecutors said Snitzler met a 17-year-old student in February and communicated with the victim through text message before engaging in a relationship with the student in March.

At about 10:45 a.m. the day of the standoff, a family member of the student called police to report the relationship.

Snitzler is facing charges including felony possession of a firearm in a school zone and misdemeanor unlawful sexual intercourse and child annoyance. If convicted, he faces up to 10 years in prison.

Snitzler has coached linemen for the football program. He is a 2008 graduate of Servite High School, where he played varsity football. He worked seasonally for the football program from 2011 through the 2016 seasons, the office of Superintendent Michael Christensen said in a statement. This spring, he volunteered to help the team with a video-replay and analysis program.