TUSCALOOSA, Ala. (AP) — Four University of Alabama football players have been charged in connection with the robbery and assault of two students, officials said Tuesday.

Campus police arrested running back Brent Calloway, linebackers D.J. Pettway and Tyler Hayes, and defensive back Eddie Williams after two robberies early Monday morning, university spokeswoman Cathy Andreen said.

Pettway and Hayes were charged with two counts of second-degree robbery. Defensive back Eddie Williams was charged with both fraudulent use of a credit card and two counts of second-degree robbery. Calloway was charged with fraudulent use of a credit card.

All four players were backups last season for Alabama, which has won two straight national titles and three of the past four.

"This is a very serious matter and we are very disappointed in the actions that have resulted in the charges against these student-athletes," Alabama athletic director Mal Moore said in a statement.

University police posted an advisory Monday saying two students reported being approached by two men who asked for a light for a cigarette. Both students said they were then hit in the head and robbed.

Williams was released on $65,000 bond, while Hayes and Pettway were released on $60,000 bond each. Calloway was released on $5,000 bond.

Police also said Williams had been arrested on a charge of carrying a pistol without a permit a day before his Monday arrest. Tuscaloosa police Sgt. Brent Blankley said in a news release that a clerk at a gas station called police early Sunday, telling officers that Williams threatened that he had something in his trunk after a fight about paying for gas.

Officers who pulled over Williams found a pistol in his pants pocket, the release said. In that case, he was released on $500 bond.