Sheriff's spokesman Tony Botti says a county roads worker was on a tractor and struck a PG&E gas line, which caused the explosion shortly before 2:30 p.m. That worker suffered critical injuries.
The sheriff's office says 15 other people, including 13 jail inmates and two sheriff's deputies, were also hurt in the explosion. Community Regional Medical Center officials say three people there are in critical condition, and a fourth is in serious condition. Four people were taken to Saint Agnes Medical Center, and three others are at Madera Community Hospital.
A PG&E spokesperson said the gas line runs north and south and it's buried, at least in the spot where the contractor struck the steel. "It was a 12-inch transmission line that was hit. We're currently still assessing the damage. We haven't figured out yet how long it will take us to do repairs," said Denny Boyles.
Transmission lines are larger than your average neighborhood gas line, with much higher pressure, which explains why we saw flames shooting so high in the air. PG&E shut off the gas about 90 minutes after the explosion and the fire started dying down immediately. The spokesperson said the explosion shouldn't affect any customers.
Also out there tonight is a team from the California Public Utilities Commission, which just last week voted to fine PG&E $1.6 billion for the deadly 2010 explosion in San Bruno.
The northbound and southbound lanes of Highway 99 were closed at Herndon Avenue, but the highway is now back open in both directions.
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