A corn snake gave a St Albans bookmakers the slip after escaping from a flat upstairs on Saturday.
Staff at William Hill in Chequer Street discovered the corn snake in their shop and warned visitors: "There is a snake in the shop! If seen, report to staff. Thank you." in hand written notes around the shop.
This is the second time the unlikely visitor has escaped from the upstairs flat, forcing the shop to close.
Rupert Adams, a spokesman from William Hill, said: "This is not the first time this has happened.
"It happened once before and unfortunately the shop was forced to close due to health and safety precautions.
"Although it comes as a bit of a shock, corn snakes are not dangerous.
"We have spoken to the tenant upstairs and asked him to make sure this doesn’t happen again."