Fourteen people were rushed to the hospital with burns after a major gas line explosion near the Fresno County Sheriff's Office gun range Friday, a fire official said.
The blast occurred behind the range about 2:30 p.m. when a county worker leading a team of inmates constructing a dirt road accidentally struck the gas line, said Fresno Fire Department spokesman Pete Martinez.
Thirty-five firefighters quickly subdued the blaze, and Pacific Gas & Electric cut off the gas supply to the line, Martinez said.
The county worker leading the team and at least one of the inmates were critically injured in the explosion, which sent a fireball 100 feet into the sky, authorities said. The inmates were part of a work program at the Fresno County Jail, Martinez said.
"I heard a whirring sound like a helicopter, then two booms and fire," said Mark Price, who witnessed the blast.
Spencer Olson was drilling for water nearby.
"My jaw dropped," he said. "I saw an enormous fireball."
The accident forced closure of Highway 99 in both directions for several hours, Martinez said.
Investigators were still working Friday evening to identify what ignited the blaze.
Martinez said the investigation was hindered by a large crater with heavy equipment demolished in the fire. Investigators were unable to speak with the county worker who was leading the team.
Fresno County Supervisor Henry R. Perea told the Fresno Bee that burns covered more than 30% of the employee's body, including his torso, legs, arms and hands.
"He is pretty lucky," Perea told the newspaper. "As the gas line was exploding, he was jumping off the equipment, so he kind of saved himself by acting quickly."
The California Public Utilities Commission sent a team to the scene of the blast, according to Terrie Prosper, a spokeswoman for the agency.
"The CPUC will conduct a full investigation of the explosion and has already coordinated with the federal Pipeline and Hazardous Materials Safety Administration," she said.
Marcum reported from Fresno.