Two 17-year-old boys were arrested Wednesday following an alleged gang fight at a middle school graduation in Pinole, police said today.The suspects, a San Pablo resident and a Richmond resident, were visitors at the evening ceremony at Elizabeth Stewart K-8 School, located at 2040 Hoke Drive, police said.Officers went to the school at about 6:40 p.m. on a report of a fight involving students and parents. Police said several people involved identified themselves as Norteno gang members.An off-duty police officer who had attempted to stop the fight was allegedly assaulted by two of the suspects, police said.The San Pablo teen was arrested for assault and an outstanding warrant, police said. He was booked into juvenile hall. The teenage Richmond resident was arrested for assault and participating in criminal gang activity, police said. He was booked and released to his parents. Anyone with additional information regarding the case is asked to call Detective Deaver at (510) 724-8941.