A "loose, dangerous animal," suspected to be an escaped big cat, was reportedly sighted in a Potsdam region on the fringes of the German capital on Thursday, police said.

Authorities are using helicopters to track what they believe is a female lion and have called on residents to stay indoors, the rbb public broadcaster reported.

According to the German tabloid BILD, security forces were also using an armored vehicle, drones and infrared cameras in the search. 

Police said veterinary specialists and hunters were also taking part in the operation to find the animal.

A police spokesman said drones were being employed where possible to avoid the usual search method of combing forest areas on foot.

On Thursday evening, a police spokesperson said that 220 officers were searching near where the animal was last seen in wooded areas near the municipalities of Kleinmachnow, Teltow and Stahnsdorf at the southern edge of Berlin.

The search is expected to continue through the night with the aid of night vision devices, the spokesperson said. 

"We will be on the job until the animal is found is found," the spokesperson added. 

Police renewed their warnings late Thursday evening, telling people to avoid forested areas around the edges of southern Berlin.

They said their officers would remain in the area overnight with the search to resume in earnest in the morning. The search on Friday was expected to be intensified with professional animal trackers scouring the forest.

Experts ponder where Berlin animal came from

"It's clear lions can't drop out of the sky, not in Germany, at least," said Professor Heribert Hofer, director of the Leibniz Institute for Zoo and Wildlife Research in Berlin.

Although it is illegal to keep big cats in Berlin, it is possible in the neighboring state of Brandenburg, Hofer told DW. 

The owner must have an expert certificate, keep and adequate private enclosure, and receive an official veterinarian check from the state.

"The costs of keeping large cats in the appropriate manner is quite prohibitive," Hofer said. "It would be somebody's rich hobby, somebody who is very rich," he said. 

Hofer added that the lion could have come from one of four places: a zoo, a circus, a legal private enclosure, or an illegal private enclosure. 

"This is the big question, which also makes it more difficult to find it, because we don't know: Was it a cat that was raised in humans by humans in close contact? Is it really a cuddly cat, or is it actually a wild animal that would rather not see humans?" he said.

If anyone should come into contact with the animal, Hofer said it is important to remain calm. 

"First of all, you would not run away screaming. You would stop and stand, and you let the animal look at you to see what you do," he said.

"And then you look at the animal to see what it does. And then it has control of the situation. And in 99 out of 100 cases, they will simply vanish."

How was the suspected lion first spotted?

Earlier, residents have reportedly received messages via warning apps. Among other things, they have been requested not to go for walks in the woods and to seek shelter in their houses or cars if they sight the animal.

Police said they had received information on the presence of the animal from witnesses who had filmed it attacking and killing a wild pig.

They said they did not know where the animal may have come from, having checked with zoos, circuses and animal shelters who all said they were not missing a lioness.

"We have deployed massive forces at the site to protect the population," a police spokesperson said.

A spokeswoman for the municipality of Kleinmachnow said children at kindergartens were not being allowed into surrounding gardens and that sellers at the market had been advised not to set up stalls at present.

"This sort of thing doesn't happen every day," she said.

 tj/wmr (dpa, rbb, AFP)

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