A BAE worker has spoken of his shock after a live worm wriggled out of a monkfish fillet he bought from Tesco Extra in Barrow.

The worker, who did not want to be named, spoke about the bizarre moment when the invertebrate began crawling out of the piece of fish when he was preparing to cook the fish.

He said: “It was a piece of monk fish that I’d got and as I’m cutting it this worm just crawls out.

“I’d bought it from Tesco Extra in Barrow on the Saturday morning and came to eat it Sunday night.

“I did post it on social media as I thought it would get a laugh, and I don’t really want to have a go at Tesco because these things happen.

“When I took it back Tesco gave me a full refund and apologised.

"Then I went to get some prawns because I obviously didn’t fancy fish at this point.”

Monkfish tails at Tesco sell for £9.20 on average.

The worm found in the monkfish is likely to have been an anisakis worm which have been known to appear on occasion in monkfish and cod meat.

Due to the life cycle of the worm, they are eaten by crustaceans which are in turn eaten by monkfish, salmon and cod, where the worm then reproduces as a parasite.

The worms usually do not survive being frozen for several days with live worms only appearing in fresh fish.

They can survive being cooked lightly, and if ingested live, they can cause serious health issues similar to food poisoning that lasts up to three weeks.

Most parasites are found while at fisheries so that the infected fish do not end up on store shelves, although they can slip through the net.

The complainant said Tesco had extended their apologies to the gentleman for the incident and were more than happy for him to return the fish.

The Mail approached Tesco for a comment but did not receive a reply by the time we went to press.

People can easily check their fish for worms by holding the meat up to a light and looking for small lines inside, once removed the fish is fine to eat.