An off-duty MTA officer is facing charges after police say he teamed up with his son to beat up a teenager in the Bronx.

Police say two boys got into a fight Thursday afternoon in Soundview.

That's when Ruben Caraballo is accused of stepping in, allegedly punching one of the boys in the ribs.

That boy's father says his son was defending another student from a bully when the fight started.

"His father got involved pushed his son on my son and told him to draw blood from my son and he also punched my son in the stomach very hard," said Sean Harris, the father of the victim.

"As a father, I didn't feel that that was the right action for him to do. I felt that it could've been mediated before."

Caraballo is charged with assault. He's a bridge and tunnel officer who has worked with the MTA since 2005.

The agency says he remains on active duty but is not allowed to carry a firearm.