St. Louis ? Missouri basketball player Kalen Grimes used the butt of a shotgun to strike a man in the face during a fight in suburban St. Louis, police said.

Details emerged Tuesday, a day after Tigers coach Mike Anderson suspended Grimes indefinitely. A spokesman for the St. Louis County prosecutor’s office said formal charges of second-degree assault were pending against Grimes, 21, Missouri’s leading rebounder last season.

Grimes’ brother, Michael, also involved in the skirmish, was struck in the head with a lug wrench. Police said no one was seriously hurt.

“I think it could have turned into some tragic incident,” Florissant Police Chief William Karabas said. “These people are going to recover. They got a bop on the head. What if somebody got shot, or got hit so hard he was killed?”

The incident happened about 3 a.m. Saturday and began when Grimes’ cousin, Ryan Fisher, and another man got into an argument over a woman at a Jack in the Box restaurant, Karabas said. The skirmish spilled over onto a Dairy Queen parking lot nearby.

Karabas said Fisher called Grimes to say he was getting into a fight. Grimes and his brother drove to the restaurant to offer help.

Kalen Grimes admitted getting out of the car, pumping the shotgun twice, then striking the man, Karabas said. The victim suffered a cut to the forehead.

Meanwhile, the brother of the man arguing with Fisher grabbed a lug wrench and used it to strike Michael Grimes in the head, Karabas said. That man has not been charged.

After the fight, Grimes and his brother drove away. An officer pulled over Grimes and arrested him without incident. Karabas said a loaded .40-caliber pistol was found in the car.

Grimes, of Columbia, did not have a listed phone number. A spokesman for the basketball team declined comment.

On Monday, Anderson said Grimes would not be allowed to train with the team, and said he “must take the necessary steps to not only earn the trust of his coaches and teammates, but the trust of Missouri’s alumni and fan base.”

Missouri began a “zero-tolerance” policy after junior forward DeMarre Carroll, a highly regarded transfer from Vanderbilt, was shot in the ankle last week during a disturbance outside a Columbia nightclub. Anderson said he wanted to assure fans that the incidents “will be dealt with appropriately.”

Grimes, a senior next season, started 24 games last season and averaged seven points and 5.6 rebounds.