A live snake has been captured on CCTV living in a sewer in Wiltshire.
The grass snake was spotted last week during a routine maintenance check of a 67-year-old sewer under Calne.
It is thought the snake, which feeds on amphibians, entered the underground network through a field or road drain in search of prey.
A Wessex Water spokesperson said it was the first time a snake had been seen in its system but that it "definitely won't turn up in people's toilets".
The South West-based utility company has been using CCTV cameras to maintain its sewerage network since the early-1990s.
But Roz Trotman, a CCTV and flow surveyor, said they were "all very shocked to see the footage" of the snake.
"We use CCTV in over 124 miles of our sewerage system and often find creatures such as bats, rats and toads," she said.
"It is the first time a snake has ever been seen in our sewers.
"We will all be on the lookout for the snake when we watch any future footage."
Reaching nearly two metres, grass snakes are the UK's largest reptile and are strong swimmers and excellent climbers.
In 2005, it was reported that a boa constrictor was roaming sewers in a block of flats in Manchester. And in 2010 a fully-grown crocodile was spotted emerging from a sewer in New York.