The St Kilda Tavern. Photo: Gerard O'Brien
A police spokeswoman said they received a report of the robbery just before 11.30am.
Two heavily disguised offenders entered the pub in Prince Albert Rd and demanded cash, police said.
"They presented a firearm at the bar staff and after being unsuccessful in obtaining any money they ran off onto Young St."
Marked and mufti police cars were parked near the St Kilda Tavern and officers were seen coming and going from the business.
The Criminal Investigation Branch (CIB) were also at the scene.
Officers could be seen investigating side streets and photographing the outside of the pub.
- Anyone who is in the area around the time of this incident and saw something which may assist police enquiries is asked to get in touch via 105, quoting event number P048618788 or contact Crime Stoppers on 0800 555 111.
