OAKLAND -- Arson investigators are probing a series of suspicious fires that occurred within a four-hour period Tuesday night in East Oakland, including five vehicles that were damaged.

The parked vehicles caught fire between 9:15 p.m. and 11:14 p.m. in the 2400 block of Havenscourt Boulevard, at 65th Avenue and Arthur Street, the 2400 block of 66th Avenue, the 5300 block of Fairfax Avenue and the 5300 block of Ygnacio Avenue.

All the fires were quickly extinguished but damage figures were not available. There were no reported injuries.

Two other fires in another part of East Oakland were also deemed suspicious.

One fire was set in a Dumpster in the 4200 block of Foothill Boulevard about 7:40 p.m. In the other blaze, which happened at 7:02 p.m., vegetation in the 3800 block of Foothill caught fire and the flames spreading to a fence. Both fires were quickly extinguished and no damage figures were available.

Authorities believe the vehicle fires might be related, but are not sure if there is any connection between those and the Foothill Boulevard fires.