The rifle magazine that a police officer lost in Napier has been found, police say.

The magazine was found on one of Napier's busiest streets - Marine Parade.

READ MORE: Cop loses rifle magazine after leaving it on car roof

The early indications were that it had not been tampered with, police said.

The gun part was lost on Wednesday after an officer "inadvertently" placed it on the roof of a patrol car and drive from Napier to Hastings.

Acting area commander of Hawke's Bay, Inspector Matt Broderick, said the mistake was "regrettable" and should not have happened.

Broderick said the rifle magazine was found this morning. An internal review of the incident was continuing, he said.

-NZ Herald