Race was a factor in a riot involving several hundred inmates Tuesday at Folsom State Prison. "White versus black, as far as I know," said Lt. Dave Zaniroli, prison spokesman. "We're in the beginning stages of investigation." Fighting broke out in the prison yard around 1:15 p.m. Approximately 600 men were getting some time outdoors, observed on the ground by a total of five corrections officers and a sergeant and from towers by five other guards, Zaniroli said. A handful of combatants were injured seriously enough for medical treatment, but none seriously, he said. Officers waded into the fray "quickly and in great numbers," Zaniroli said, but fighting reportedly spread from the yard into two buildings. No officers were injured. The sizable prison yard, home to a baseball diamond, courts for basketball and handball and a running track, has a population cap of 700 inmates, Zaniroli said. In prison, even slight issues are magnified, he said. "If you look at the history of prisons, a lot of things ensued from stuff that, in reflection, we'd say, 'I don't believe it,'" Zaniroli said. "The north-south Latino gang rift started over a pair of tennis shoes."