AN URGENT alert has been issued by police after a man was spotted carrying out a sex act outside a primary school.

Police said they have received reports of a man conducting a sex act near St Matthew's C of E Primary School in Stretford.

Officers attended the Poplar Road site but the alleged offender had already left the scene.

Scenes of Crime Officers (SOCO) have taken forensic evidence away for testing.

Greater Manchester Police's Stretford team posted about the incident: "*Alert* We have received a call of a male masturbating near to St Matthews Primary School, Stretford. Officers have attended but he already left. He has left, shall we say, evidence at the scene, which our SOCO officers have seized. This will be tested and an arrest imminent."