A rep for the Las Vegas Police Department tells TMZ ... Pia was cited for leaving the scene of a traffic accident last Friday.

Sources tell us ... Zadora was driving a white Cadillac Escalade Hybrid when she struck a red BMW. We're told Pia did not stop to exchange information, but rather she just drove off.

According to our sources, the other driver followed her back to her gated community and called the police. Cops came and Pia was eventually cited for leaving the scene of an accident.

Despite confirmation from the cops, a rep for Pia insists the actress was NOT cited for hit and run ...but rather failure to report an accident.

The rep says Pia acknowledges there was a bump ... but claims she didn't feel the impact and that's why she left the scene ... insisting there was never an intention to break the law.