Hundreds of venomous black widow spiders are believed to have hatched out in a shipping container full of tyres that was being transported from Arizona to Norwich.
The Mirror reports that pest control experts were called to Fendercare Marine in Norwich after workers spotted the distinctive creepy crawlies.
Mark Cook, group HSE manager for Fendercare Marine, told EDP24: "It is not something you expect to see, especially in the outback of Norfolk. Our guys are used to checking for wildlife, so when they spotted the spiders they shut the doors to keep them trapped in."
Initially, workers had no idea how many spiders were inside the container, but they removed two for identification purposes. The spiders are easy to identify thanks to the red, hourglass-shaped mark on their abdomens.
Black widows are the most poisonous spiders in North America. Although their bites can be fatal, in most cases they are not.
Mr Cook added: "The little creatures have a bad reputation with people thinking their bite is immediately fatal, but generally people are just fairly sick."
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