A cyclist killed in a collision with a ute at Pakenham this morning was an off duty police officer.

The male sergeant from the Southern Metro Region was riding along the Princes Highway when he was struck just before 9am on Friday.

He died at the scene.

A 58-year-old Pakenham man is helping police with their inquiries.

Anyone who witnessed the crash or has any information is urged to contact Crime Stoppers on 1800 333 000 or submit a confidential crime report at www.crimestoppersvic.com.au