PLEASANT HILL (CBS SF) — A series of fires along a popular walking and cycling trail in Contra Costa County have been determined to be intentionally set, according to fire officials.

A spokesman with Contra Costa County Fire Protection District confirmed that arson was the cause of multiple fires along the Iron Horse Regional Trail Monday afternoon.

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Crews responded to the fires reported shortly before 3 p.m. that dotted the trail between the cities of Pleasant Hill and Concord between Sherman and Brookview drives. The fire district wrote on Twitter shortly after 3:15 p.m. that the fires had been contained and nearby
structures were no longer threatened.

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People are asked to avoid the Iron Horse trail and surface streets in the area while crews mop up and do other work in the area Monday afternoon.

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The Iron Horse Regional Trail spans 32 miles from Concord south to Pleasanton, according to the East Bay Regional Park District.