Two men have been shot, killing one and seriously injuring the other, after a public shooting took place in western Sydney overnight.

About 11.50pm Thursday, emergency services rushed to a service station at the intersection of Pitt and Neil streets in Merrylands after receiving reports of gunshots.

Officers attached to Cumberland Police Area Command found a 39-year-old man suffering a gunshot wound to his buttocks.

Paramedics treated the man before taking him to Westmead Hospital in a stable condition.

Soon afterwards officers located another man, believed to be about 40, with critical gunshot injuries near the intersection of Fox and Robert streets in Holroyd.

He died at the scene and is yet to be formally identified.

Two crime scenes were established and will be examined by specialist forensic police on Friday.

A staff member from the Caltex service station located at the Pitt and Neil street intersection said the store was closed at the time and no damages were reported.

Extracted in full from: Merrylands, Holroyd shootings: One dead, another seriously injured | Daily Telegraph