CCTV images of two men who threatened staff and stole money from a Sandwich travel agency have been released by police.
It is believed that the men, who were wearing high visibility tabards, were in the town for several hours prior to the robbery on Monday morning.
Detective Constable Tom Wilson of the Kent and Essex Serious Crime Directorate said: "The men may have been in the town since 6.30am. Perhaps they were seen by people on their way to catch a train and going to work."
The two entered the King Street business at about 10am. One of the men had a gun and pointed it at the two women members of staff.
The women were forced to hand over money, both cash in various currencies and travellers' cheques, before the men walked out of the travel agency towards Short Street.
The men are described as black and one was taller than the other. They had balaclavas over their faces and had dark-coloured sports bags over their shoulders. One of the men was wearing a white hooded top and dark trousers. The other was wearing a dark hooded top and trousers. His gloves did not match as one was red.
Anyone with information is urged to contact Kent Police on 01303 289353 or 101, giving reference number ZY/35204/12. Kent Crimestoppers can be contacted anonymously on 0800 555 111.