A three-alarm fire ripped through the vacant Mexican American Community Services Agency youth center at 600 Sinclair Drive in San Jose’s Mayfair district shortly after 1 a.m. Friday, according to the San Jose Fire Department. Flames engulfed the structure before firefighters arrived, and officials said the building appears to be a total loss. No injuries were immediately reported, and investigators have not yet determined the cause, though initial reports indicate the blaze may have started outside the facility. The Renaissance at Mathson school, which sits adjacent to the property, cancelled classes for the day because of safety concerns, the Alum Rock Union School District said. Community members had recently urged city officials to spare the long-shuttered center from demolition, arguing the 1950s building could be repurposed for youth programs. Fire crews expected to remain on scene through the morning to put out hot spots and begin an investigation.