PORTLAND, Ore. — Someone dumped what appears to be latex paint on more than 20 Portland police cars Tuesday morning.

Police said it happened at about 5 a.m. in the 400 block of Northeast Emerson Street.

Many of the affected cars are school resource officer vehicles, which means those officers won't be available at neighborhood schools until the cars can be cleaned.

Police said the bureau is already experiencing a vehicle shortage.

Officers will review surveillance cameras in the area and try to track down the suspect.

Investigators said it was unclear whether the vandalism was related to May Day, but Portland Police Bureau Capt. Charlie Fender said the connection wouldn't surprise him.

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Anyone with information about this incident should contact the Portland police non-emergency line at 503-823-3333.