The mayors of San Francisco and neighboring Oakland, California, on Sunday vowed to keep the peace at each city's arenas after two shootings and a beating followed a preseason football game at Candlestick Park, said a CNN report.

"Violence will not be tolerated in either of our stadiums," San Francisco Mayor Edwin Lee and his Oakland counterpart, Jean Quan, said in a statement issued Sunday. "The incidents at Candlestick Park last night after the San Francisco 49ers versus Oakland Raiders game are completely unacceptable and will be prosecuted to the fullest extent of the law."

Police are still investigating whether team rivalry is to blame for the incidents, which occurred late Saturday in a Candlestick Park men's room and the stadium's parking lot. And at least one fight broke out in the stands during the game.

The mayors said the games "are family events, and the types of images we witnessed last night have no place in our arenas."

"Public safety remains our top priority, and we are doing everything we can to ensure that when fans come to our cities and our sports arenas they have a positive, safe and enjoyable experience," Lee and Quan said. "Our thoughts are with the victims and their families for a speedy recovery."

The shooting victims were men ages 22 and 24, each found in different parts of the parking lot late Saturday. It wasn't clear whether the shootings were connected, said a CNN report.

It was unclear whether the shooting victims had attended the game, and whether they favored either team. The older man was hospitalized with life-threatening injuries, while the other suffered less serious wounds, the report said.

And a 26-year-old man was found beaten and unconscious in an upper-level men's room during the game. His injuries are also considered life-threatening, Andraychak said.