Two chimpanzees who escaped from their owner's back garden went on a rampage in Las Vegas.
Las Vegas police said they had no choice but to kill one chimpanzee and tranquillise the other after the "agitated" animals roamed the streets.
Officer Laura Meltzer told msnbc.com: "They were acting aggressively. We had reports of two chimpanzees on the loose and one was pounding on a police car."
According to the Telegraph, neighbourhood resident David Plunkett saw the male chimp jump on top of a police car, with an officer inside.
Las Vegas police spokesman Marcus Martin said: "We tried to establish a perimeter until the experts arrived. But at least for the first animal, they couldn't get there in time."
The chimps were on the loose for around 30 minutes before the 150-pound male was shot and killed.
The female was shot twice with a tranquilliser dart before she could be returned to her cage.
One woman rang police to say a large chimpanzee was on top her car, while Mr Martin said officer saw the chimps climb into the driver's side of a black sport's car and then out of the passenger side, as well as pounding numerous vehicles.
Police warned residents through Twitter not to leave their cars or their homes.
Defending the decision to put one down, Officer Martin said: "We have an exotic animals policy. It's to treat them as humanely as we can. But immediately you recall the woman who has no face because of a chimp. The officer knew they were dangerous animals and he was the last line of defence with citizens behind him."
Officer Martin was referring to Charla Nash, who was left completely blind and disfigured by a chimp attack in Connecticut in 2009.
Meanwhile, just last month, a man was left fighting for his life after two chimpanzees attacked him and dragged him for more than a mile at a remote game reserve in South Africa.
The man, believed to be student from the US studying chimp behaviour, was bitten multiple times at the Jane Goodall Institute Chimp Eden.
Witnesses say the animals grabbed the victim by his feet and yanked him into their enclosure.
Man mauled by chimps at South Africa Game reserve
Woman attacked by cheetahs in South Africa
Man killed by lion in Johannesburg
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