Lions and drones and boars, oh my! Police race to find 'pet' on the loose in Berlin

Police were first alerted by two members of the public who recorded mobile phone footage of what appeared to be a wild boar and a lion chasing each other.

Police patrol during a search for a escaped lion near the village of Kleinmachnow in the south of in Berlin, Germany. Source: AAP / STRINGER/EPA

A presumed lioness is on the loose in Berlin, where residents in some areas have been warned to stay indoors as scores of police try to track the animal down.

Police, who believe the animal is an escaped pet, were first alerted about midnight Wednesday by two members of the public who recorded mobile phone footage of what appeared to be a wild boar and a lion chasing each other.

No boar carcass has been found.

"Even experienced officers had to conclude that it was probably a lioness," a police spokesperson told local broadcaster RBB.

German authorities warned people in the southern suburbs of Berlin about a potentially dangerous animal believed to be a lioness on the loose. Source: AAP / STRINGER/EPA

Authorities believe the wild cat could currently be asleep in one of the many lakeland forests in Brandenburg, the state that surrounds Germany's capital.

"We recommend that people shouldn't leave the house to walk and especially not to go jogging in the forest," said Michael Gruber, mayor of Kleinmachnow, a municipality on Berlin's southwestern border where the animal was first spotted.

An operation to track it down using two helicopters, drones and infrared cameras was expanded in the early hours of Thursday as a hundred police officers joined forces with hunters and vets.

They would aim to tranquilise and capture the animal and only kill her if she posed a danger to people, Gruber said, adding that the search was now concentrated in the municipality's northeastern part.

Since no zoos or circuses have reported a missing lioness, police believe she must be an escaped pet.

Police cars line the streets of a residential area in Teltow as a wild animal that escaped during the night in the south of Berlin could be a lioness, according to police. Source: AAP / Fabian Sommer/DPA

Animal rights groups criticised successive governments for failing to ban the practice of keeping wild animals as pets.

"Over the past two decades there have been repeated cases of big escaping from homes and circuses," said Peter Hoeffken of rights group PETA.

"Despite countless warnings, politicians have failed to ban the keeping of exotic wildlife."

Circus keeper Michel Ramon Rogall said there was no circus with wild animals currently on the road in eastern Germany, "and they wouldn't escape either (if there was)".

Five lions escaped from an enclosure at Sydney's Taronga Zoo last November, sparking an emergency and forcing the iconic site into lockdown.