LONDON -- British police say a tiger that killed a female zookeeper has not been killed by officials, and the investigation into the deadly incident continues.

Few details have been released about the encounter at Hamerton Zoo Park that claimed the life of 34-year-old zookeeper Rosa King, who worked at the zoo for roughly 14 years. The zoo, 130 kilometers (about 80 miles) north of London, has been closed.

Witnesses say they heard screams coming from the area and they tell of frantic employees trying to lure the tiger away from its victim with pieces of meat, CBS News foreign correspondent Debora Patta reports.

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Zoo officials say their staff are "extremely distressed" over the death of their colleague.

Rosa King CBS News/YouTube

Cambridgeshire Police said Tuesday that the tiger was unharmed.

The zoo described Monday's encounter with the tiger as a "freak accident." The zoo was evacuated as a precaution but officials said the public was never at risk and the tiger did not escape.

Animal expert Jack Hanna tells CBS News a tiger is a "very powerful animal" and "a solitary cat."

He says these animals retain their natural instincts even if they have spent all their lives in captivity, so while a fatal encounter like the one at the Hamerton Zoo is tragic and unfortunate, Hanna says it is hard to place the blame on the tiger.

"When these kind of things happen, the protocol has either been broken, or it's someone else's mistake. It's very simple. It's not the animal's mistake at all. I cannot blame anything that happens in the zoological park on the animal, basically. They are who they are. So I must say, this is human failure at the park when this happens," Hanna said.