Workers at historic pub in Sydney's west left traumatised by hold-up

A 31-year-old man is being questioned at Blacktown Police Station this evening, accused of involvement in an armed hold up at the Alroy Tavern in Plumpton this morning.

Just after 10.30am today, two men wearing balaclavas stormed the tavern demanding cash.

Police believe the pair got away with up to $5000 in cash, while a third man was waiting in a blue Subaru WRX outside.

The armed men left the tavern and travelled to a unit block on Artillery Crescent at Seven Hills.

A police tip-off by a nearby resident led authorities to the home, and within minutes arrested the 31-year-old.

A car believed to be the getaway car involved was taken away for forensic examination.

At least one man is still on the run from police.

Anyone with information about the robbery is urged to contact Crime Stoppers on 1800 333 000.