Jake Price found the huge reptile dumped at a lay-by beside the A3 in Cobham, Surrey on Tuesday.
The 21-year-old, from Southampton, Hampshire, noticed a clear box hidden beside a bush and was startled when he realised he had stumbled on a Burmese python.
Jake and a police officer lifted the snake – which reportedly weighed at least 30kg. (C) Jake Price
Images show the animal coiled around itself while contained inside a 64L plastic tub.
The yellow and white snake, which weighs around 30 – 40kgs, appears to be crammed into the box with very little room to move.
An image shows a police officer and Jake lifting up the clear box to examine the snake inside.
A third image shows another officer standing alongside the snake – this time with the lid removed from the box.
Surrey Police posted about the discovery on Facebook on Tuesday, writing: “We picked up this unusual passenger on the side of the A3 in Cobham today. A large Burmese python.
“If anyone has seen any sssssssupicious activity in the area then please contact Ssssssssurrey Police quoting reference P21268667.
“We’d love to reunite them with their owner.”
The post has gained over 650 likes and more than 600 comments from shocked social media users.
Beth Shafiq said: “Poor snakey. Definitely way too cold, bless it, glad it’s safe now. Hoping it wasn’t dumped.”
Gareth Fieldus said: “Personally I’d say please don’t try to reunite it with its previous owner.
“If it’s this large and escaped, and the previous owner didn’t notice, that’s obviously bad.”
Maxine Creedon Barrett said: “Not sure how someone could lose this!”
Vicky Marsh said: “He definitely would not have liked being outside in this weather, hope he recovers.”
Magdalena Sulkowska said: “Poor thing must be freezing. I hope you can give him/her care until the owner is found, or until it’s possible to find a new owner.”
And Jo Bowman added: “Should leave it in the van when picking up custody visitors, would certainly keep them a bit subdued.”
Police officers took the Burmese python to a local vets. (C) Surrey Police
Speaking today, Jake, who discovered the snake, said: “Me and my colleague had to take a break at about 12:30 on Tuesday.
“We were going to go into the services 10 minutes up the road but we saw this lay-by and decided to stop there.
“We got out of the vehicle and saw a plastic box sort of tucked in by a bush so on closer inspection we found that it was in fact a Burmese python that was about 12-13ft long.
“At first we were startled and shocked by it but after five minutes we were just gobsmacked at the fact someone could leave the poor animal on the side of a busy road, especially when it needs heat to survive.
“I called the police as soon as I could and waited two hours for them to come as I wasn’t going to leave the snake there to just die or for someone else to come and take it.
“We finished work late that day because of this but saving an animal’s life was definitely worth it.”
Speaking today, a spokeswoman for Surrey Police said: “‘Officers were called to the Cobham Junction of the A3 at around 12:40pm on Tuesday (14 December) following reports of a large snake being found in a box by the side of the road.
“The snake was collected and taken to a local vets.
“An investigation is ongoing to locate the owner of the animal and anyone with any information is urged to contact us quoting reference number PR/P21268667.”
Burmese pythons are one of the largest species of snakes in the world.
In the wild the snakes usually grow up to 16ft, with unconfirmed specimens reportedly reaching over 23ft.
Typically found throughout southern and south-east Asia, Burmese pythons are excellent swimmers and usually live near marshes and swamps but can also be found in trees.
Whilst often sold as pets due to their easy-going nature, they have a rapid growth rate, and can exceed 7ft in length in a year.
Human fatalities from non-venomous snakes are very rare, and have been reported to average one or two per year worldwide.
They are listed as Vulnerable on the IUCN Red List.