A pest controller was stunned to discover a rat the size of a dog lurking in a country home.

The sewer rat was anything but common, measuring a staggering 55 cm long when it was discovered inside a family home in Normanby, North Yorkshire, Metro reported.

Photos of the giant dead rat have made the rounds on social media, with users horrified - and left questioning how the creature managed to grow so large.

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“Looks like a dog,” one Facebook user wrote.

“Is that Splinter from Teenage Mutant Ninja Turtles, look at the size of it,” another wrote.

Two local councillors have raised calls for action. They say this rat is just an example of the area’s “overflowing” rodent population.

In a Facebook post, Tory councillors David Taylor and Stephen Martin, called on the local Redcar and Cleveland Council to carry out a full vermin study.

“As many of you have seen, the rat infestation we raised has now made national headlines,” the statement said.

“It’s clear this needs a joined-up response — from government, local councils, housing providers, landlords, the NHS, commercial developers, and the water board. We need a proper vermin control strategy and fast.”

“This situation should never have been allowed to get this bad. There’s no doubt plenty of blame to go around, but what matters now is what we do next to stop it getting worse.

They called for a “borough-wide vermin survey” to identify hotspots, and a “proper treatment plan”.

Calling the rat problem an “outbreak”, they also seek an “immediate, intensive response in Eston, Normanby, and the wider area”.

The pair went on to critique the Labour administration of the local council, claiming no one had “been in touch”.

Councillors Paul McInnes, Paul Salvin and Curt Pugh also posted a statement to Facebook calling for the same actions.

“This hasn’t happened overnight. Two years ago, Councillor Salvin worked with then-MP Jacob Young to pressure Northumbrian Water into taking action on the issue,” the post said.

“Their intervention made a difference and reduced the number of rats at the time, but notably, the Council declined to get involved.

“Now, the rats are back, and in even greater numbers.”

Social media users could not believe the size of the rat, but some say they have also been shocked by rats in their local area.

“You should see the size of some of them up bankfields allotments, they are the size of cats,” a Facebook user wrote.

“They are everywhere we had them in our attic last year, Eston baths area we still have them in the gardens now even though we all put poison down,” another wrote.

“That rat is bigger than my grown cat,” another wrote.