The San Francisco 49ers have announced that Ray McDonald has been released from the team amid concerns over his off-field behaviour.

The defensive end, who missed time in the pre-season after being arrested on suspicion of domestic violence, is now being investigated by the San Jose Police Department over an alleged sexual assault.

General manager Trent Baalke said in a statement: "I can say that we have had multiple discussions with Ray over time and there's been things that have been discussed with him.

"And there was a plan that was put in place and this is a situation that has gone against that plan."

No charges have been filed against McDonald, who had been with the 49ers since being drafted in 2007.