Keepers at the safari park, in Merseyside, said they suspect visitors have been giving the animals knives, screwdrivers and even a chainsaw "for a laugh", The Mirror reports.
But the park has denied the baboons are armed and dangerous.
Cars have been damaged by baboons climbing on top of them, ripping windscreen wipers and wing mirrors off as they drive through the enclosure. One park worker reportedly said: "The baboons have been found with knives and screwdrivers. I do wonder if it’s some of the guests handing them out.” The worker added: “We’re not sure if they are being given weapons by some of the guests who want to see them attack cars, or if they’re fishing them out of pick-up trucks and vans.
“They will literally go into people’s toolboxes and carry them around. One of the baboons was seen lugging around a chainsaw.” A car mechanic, living in Sale, said: “I’ve had two customers this year who became victims of those baboons “The kids start chirping up saying they want monkeys all over the car, and the next thing you know, you’re driving home with no registration plate.”