PLEASANTON (CBS) — A small grass fire drifted smoke across the Alameda County Fair, prompting the shut down of some rides, and closed a major road in Pleasanton Wednesday afternoon, a deputy fire chief said.

The fire along Bernal Avenue between Valley and Pleasanton avenues was reported at 2:53 p.m., according to Livermore-Pleasanton Deputy Fire Chief Joe Testa.

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Firefighters had it under control in about 20 minutes, and it only burned about an acre of grass. But firefighters had to shut down Bernal, a major four-lane street, for about 30 minutes.

Heavy smoke from the fire drifted into the Alameda County Fair nearby, prompting fair operators to temporarily shut down some rides, though it wasn’t at the request of firefighters, Testa said.

It was started by landscapers working in the area. No structures were threatened and no one was injured.

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Livermore-Pleasanton firefighters put out a separate 2-alarm fire in Livermore earlier in the day.

That fire was reported at about 12:45 p.m. near the Portola Avenue on-ramp to Interstate Highway 580.

High winds caused it to spread and firefighters called a two-alarm response, Alameda County Fire Department spokeswoman Aisha Knowles said. It was under control by 1:30 p.m.

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The fire burned 2 acres. No one was injured and no structures were nearby, Testa said. Its cause is under investigation.