Snake found living on Southern Rail train at Selhurst station

British Transport Police officers called Gareth North from Mitcham Zoo to help with the reptile at around 11pm on December 16.

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Photos show the snake on the floor of the train carriage at Selhurst Train Depot - it had been travelling between London, Kent and Sussex.

Gareth North from NCRW and Mitcham Zoo (Image: Mitcham Zoo)

Gareth North told the News Shopper: "It's a four-foot corn snake, its sex is currently unknown.

"It has superficial injuries from being trapped in the heat grate trying to squeeze through.

"The injuries are old, not new when found, which suggests it has been on the train carriage for some time.

"There are possibly two reasons its managed to escape on the carriage.

"Firstly, it escaped from a travel container or bag while being transported by its owner - this is the most likely reason.

"Or it has been dumped on a train hoping it is found before it gets cold.

"This is highly unlikely as abandoned or dumped retpiles are less than 1% with the data the NCRW has taken - this is based on the percentage of animals in and their reasons.

"The corn snake is currently well - it was hungry and dehydrated but doing okay."