Police are investigating, following an armed robbery of a service store in Blacktown this morning.

About 4.15am, police from Blacktown LAC attended a service station on Richmond Road following reports an armed hold-up.

Initial investigations suggest two men, one armed with a handgun, entered the service station before allegedly threatening the attendant and demanding cash.

One of the men allegedly hit the attendant in the back of the head, before an amount of cash and cigarettes was taken and the pair fled the scene.

A crime scene has been established and investigations are continuing.

Police are hoping to speak with two men who may be able to assist with inquiries.

One man is described as African in appearance, 175 to 180cm tall, with an athletic build. He was wearing a black bucket-style hat, black and white chequered long-sleeve shirt, light coloured cargo pants, joggers, and was carrying a handgun.

The other man is described as African in appearance, 180 to 185cm tall, with a slim build. He was wearing a black long-sleeve shirt, black pants, blue vest, and white shoes.

Police are urging anyone with information in relation to this incident to call Crime Stoppers on 1800 333 000 FREE or use the Crime Stoppers online reporting page: https://nsw.crimestoppers.com.au/ Information you provide will be treated in the strictest of confidence. We remind people they should not report crime information via our Facebook and Twitter pages.

Extracted in full from NSW Police.