Singer Lester Chambers is set to file a civil suit against Hayward, Calif, in the wake of an attack at a blues festival in the city.

Chambers had just dedicated a song to Trayvon Martin when 43-year-old Dinalynn Andrews-Potter of Barstow came on stage and attacked the 73-year-old R&B singer at the Hayward Russell City Blues Festival.

He suffered bruised ribs and a hip injury as a result of the attack and was forced to cancel planned performances.