What started as a Mass remembering a Latino baseball star and humanitarian quickly took a violent turn as an auxiliary bishop was assaulted at the Newark cathedral Saturday.

Newark Auxiliary Bishop Manuel Cruz was offering the opening prayers of the Mass when a man wearing a white robe over a red suit left his pew, approached the altar, and punched the bishop in the face, according to local news outlets.

The bishop fell backwards on the altar. He was taken to the hospital for treatment, although officials say his injuries are not serious.

A 48-year-old Newark man has been arrested and charged with assault, according to NJ.com. Officials did not speculate on a possible motive.

The Mass – which was being held at the Cathedral Basilica of the Sacred Heart – was intended to commemorate the 44th anniversary of the death of Roberto Clemente, a Puerto Rican professional baseball player.

In addition to making the National Baseball Hall of Fame, Clemente was known for his humanitarian work. He died in a plane crash in 1972 while on his way to deliver aid to earthquake victims in Nicaragua.

After Bishop Cruz was assaulted, the Mass was rescheduled for the next day at a nearby church, according to TapIntoNewark.com.

"We are thankful that law enforcement officers were able to apprehend the assailant," archdioceses spokesman James Goodness told reporters. "This is not something that we expect to happen in any of our churches."