An armed robber threatened staff at Thomas Cook in Wallington Square with a knife and stole foreign currency.
Police were called to the Wallington Square travel agent shortly before 2.30pm by staff at a neighbouring shop who heard commotion.
A man entered the shop through the front door and threatened staff with a knife before leaving through the back door.
The suspect wore a black coat and a black and white beenie hat.
The same travel agent, situated off Woodcote Road, was robbed in August last year in similar circumstances. On that occasion, a man threatened staff with a weapon believed to have been a machete or axe.
If you have information that could help police you can call 101 or the charity Crimestoppers on 0800 555 111.
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