Gas leak forces evacuations, closure of De Anza Boulevard in Cupertino

A major thoroughfare in Cupertino is closed late Thursday afternoon due to a gas leak, according to the Santa Clara County Fire Department.

The gas leak is on De Anza Boulevard, a fire department spokesperson said. The southbound lanes of De Anza Boulevard are closed between Mariani Avenue and Stevens Creek Boulevard. 

Four office buildings were evacuated. 

Pacific Gas & Electric clamped the leak at around 6:40, fire officials said. Southbound De Anza was estimated to reopen at 7:30 p.m.

The fire department said city workers, Santa Clara County Sheriff's Department and PG&E remain at the scene. 

It is not known what caused the leak. 

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KTVU contributed to this story.