The biggest zoo in Paris went into lockdown today after around 52 ‘large and potentially very aggressive baboons’ escaped from their enclosures.

All were seen running amok in the French capital’s Zoological Park, in the Vincennes woods, soon after midday, but it is thought just four remain on the loose after 48 of them were recaptured.

‘It’s not known how they got out, but everything is being done to try and get them under control,’ said a source at the zoo, which opened in 1934.

‘The whole area has been shut down, with only trained professionals involved in the security operation.

‘They include three operatives with rifles who will be able to stun the animals if necessary. Many police and vets are also in attendance. Baboons are large and potentially very aggressive.’

Baboons are not naturally a danger, but can attack humans and cause serious injuries if they feel they are being threatened.

The public had been warned the evacuation was necessary because the animals can be unpredictable when stressed.

‘They are stronger than us,’ officials warned.

An official at the zoo said the remaining four will soon return since the dominant males have already come back.

Some may have escaped into nearby play areas and other recreational facilities, but it is unlikely they have got out of the zoological park itself, which covers 36 acres.

‘They are almost certainly all in the park woods, but anybody in the area needs to keep a look out,’ the spokesman added.

Nearby roads have been closed down, with checkpoints being set up using police patrol cars.

The alarm was raised late this morning when a vet noticed a baboon in a service corridor.

An emergency plan was immediately triggered just after noon to make sure the monkeys did not come into direct contact with visitors, who included many young children.

Last June, two potentially ‘dangerous and aggressive’ monkeys managed to escape from their enclosure at Marwell Zoo in Winchester, Hants.

Visitors were barricaded inside building while keepers recaptured the macaques – one of which was pictured casually sitting on top of an enclosure.

Guinea baboons, originated from West Africa, are classified as a ‘near threatened’ species by the International Union for the Conservation of Nature.

Visitors can usually admire them around the zoo’s ‘Big Rock’ that towers over the Bois de Vincennes park, in eastern Paris.

Paris last experienced an animal-on-the-loose alert when a tiger briefly roamed the city after escaping from a circus cage last November. The beast was shot dead.