Seniors, take notice. Here’s a new way to shut down a school for a few days: Fill it with venomous spiders.

A school in the Forest of Dean (that’s in Britain, if you couldn’t tell by the name) shut down after false widow spiders — “Britain’s most venomous,” the BBC says — showed up in the building. They’re not huge spiders, but, at one inch in diameter, they’re big enough. They didn’t bite any one at the school, and, according to the BBC, they’ve never actually killed anyone in Britain. But if you’re bitten by one, expect “severe swelling, chest pains and tingling of fingers,” which sounds less than pleasant. The Forest of Dean school is going to solve its spider problem by fumigating the place.

So, would sending a crop of false widow spiders into the hallways make a good (if risky) senior prank? Quite possibly, because despite their nasty bite, “they do not move very quickly and are not aggressive,” says the BBC. In other words, the school would definitely have to deal with them, but there’s not a huge chance anyone would actually get hurt. Except for the spiders, of course, who would likely end up dying in a cloud of chemicals. Do you really want that blood on your hands?

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