BALTIMORE (AP) — Baltimore has started activating new speed cameras that replaced cameras blamed for issuing false tickets.

City officials say all 83 speed cameras installed by a previous vendor are to be replaced by the end of March.

Transportation director Frank Murphy says drivers cited by the defective cameras will get refunds. And he says the new vendor is testing and calibrating the new cameras as they are installed as well as training city officials who will sign off on citations.

Murphy says the police department will also add more officers to review the citations. The transportation director told a local news station that the city also plans to replace all red light cameras, but those cameras have not been blamed for being inaccurate.

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