The incident happened at around 2.30pm on December 7 at the HSBC branch in the High Street, police confirmed.
According to police, a man walked into the bank and demanded £4,000 or warned he would ‘burn down the branch’.
When police were called, the man ran from the building.
The suspect is described by police as white, approximately 6’, of slim build with dark hair. His face was concealed by a black hooded top and a face mask. He was also wearing a green puffer jacket, black trousers and dark trainers with a white sole.
Anyone who witnessed the incident or has any information is asked to report it online or ring 101 quoting serial 774 of 07/12.