OAKLAND (CBS SF) – The California Highway Patrol has contributed two helicopters and several patrol cars to assist Oakland police in the search for a possibly armed suspect in the city’s Dimond District Thursday evening, a CHP officer said.

The search began just before 6 p.m., according to Oakland police Officer Reginald Brown.

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CHP Officer Sean Wilkenfeld said the incident started in Oakland and Oakland police are taking the lead in the search.

Brown said he did not have information on why officers were pursuing the vehicle or where the chase started but said it ended in the 3400 block of Dimond Avenue.

One witness said several streets in the area were blocked off.

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Wilkenfeld said CHP has assisted by establishing a perimeter for the search and said the agency has “a ton of cars” in the area.

As of around 7 p.m., Brown said the incident was still considered an “active investigation.”

No further information was immediately available.

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