It was reported that at around 11.30 am a masked male, carrying a suspected firearm, entered the premises and threatened members of staff.
The male made off empty handed.
He is described as being approximately 5’10” tall, of medium build and had a black skeleton mask covering his face.
He was wearing a black jacket, grey jogging bottoms, white trainers and was carrying a black coloured backpack.
Detective Sergeant Corrigan is appealing for anyone who witnessed the incident or anyone with information that could assist the investigation to contact detectives in Musgrave Police Station on 101, quoting reference 422 28/08/18.
Alternatively, information can also be provided to the independent charity Crimestoppers on 0800 555 111 which is 100% anonymous and gives people the power to speak up and stop crime.