BENICIA (CBS SF) — A 4-alarm grass fire burning along both sides of Interstate 680 just north of the Benicia Bridge Monday afternoon forced lanes of the busy East Bay freeway to be closed for about an hour, according to the California Highway Patrol.

Benicia Fire officials said the Clock Tower Fire was first reported at 1 p.m. and quickly spread over 4 acres, jumping the freeway, threatening structures and forcing Union Pacific Railway to shut down traffic on its nearby tracks.

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While the cause of the fire was unknown, fire officials said it started near a homeless encampment. Dozens of firefighters were being sent to the scene to fight the fire. Air tankers were also making drops on the blaze.

There have been some preliminary evacuations of residents on both Oak Rd. and Park Rd.

Drivers were told to expect delays and avoid the area.

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Fire Near Benicia

Aerial of the “Clock Tower Fire” burning near Benicia Bridge, July 6, 2020. (CBS)

Caltrans confirmed shortly before 4 p.m. that three southbound lanes of I-680 north of the bridge had reopened. One southbound lane remained closed.

About a half an hour later, Solano CHP reported that all lanes had been reopened.

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