ARMED robbers threatened a security guard with a knife when they stole cash from a post office.

The guard was delivering the cash box at the post office on Haydock Street, Earlestown, when he was approached by two crooks, one of whom was armed with a knife.

The offenders snatched the cash box and headed towards the back of the post office, where it is believed they got into a blue Ford Escort.

Both offenders are between 18 to 22 years old and of slim build. One of them had drawn features, short fair hair and was wearing a grey tracksuit. The other had short, cropped hair and was wearing a black hooded top.

Detectives are appealing for witnesses to the robbery that happened at about 11.15am, on Monday, January 17, to contact Crimestoppers on 0800 555 111.