The Burmese python was first seen more than a week ago in Stapleford Woods, which is near the Lincolnshire border, by a couple who were walking in the area.

The Royal Society for the Prevention of Cruelty to Animals is searching for the reptile, which is not considered dangerous.

But the public is being asked not to tackle the snake, which has been described as being as "wide as a football".

Walking dog

RSCPA inspector Ian Callingham said: "We've had no joy finding the snake, but we are continuing to look for it.

"I understand a lady was walking her dog when she saw the snake, and it really frightened her."

"Her dog scared the snake away, but it is probably surviving by eating small mammals or rodents."

"It is not venomous, it is a constrictor so it asphyxiates its prey and eats them whole."

Villagers at a local pub expressed some concern about the snake, with one of them saying: "It certainly has people talking, and I certainly wouldn't want to come across it."

The RSPCA says the snake was probably abandoned in the woods after it became too big for its owners to look after.