Police in Prince George's County, Maryland, are installing cameras...to watch their cameras.

Six speed cameras in Maryland have been vandalized since April, WTOP reported.

The cameras cost $30,000 to $100,000 to replace, so police have started installing surveillance cameras designed to catch vandals in the act.

A dozen of the new cameras will be in place by the end of the month, WTOP reported.

Police call it a matter of public safety, not an attempt to generate profit.

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