London Zoo has launched an investigation after a 29-stone western lowland gorilla escaped from its den on Thursday evening (October 13).

Kumbuka, an 18-year-old gorilla who was moved to the zoo in Regent's Park in 2013, got out of his enclosure into a "non-public keeper area" of the complex at 5.13pm.

The animal was captured using a tranquilliser dart fired by vets and is said to be awake and well.

A spokesperson for the zoo said: “Staff responded immediately and the 18-year-old gorilla – named Kumbuka – was tranquillised by vets and returned to his den, where he was soon awake and well.

“It is not yet confirmed how the incident occurred and a full investigation is under way to determine what happened.”

Kumbuka the gorilla escaped from his enclosure on Wednesday evening

Reports of an escape zoo first circulated on Twitter at around 5.30pm after visitors were told to get inside quickly by keepers.

A video appeared to show armed police at the zoo searching for Kumbuka.

Video thumbnail, Visitors locked in at London Zoo after gorilla escapes
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Visitors locked in at London Zoo after gorilla escapes

For a fact file on Kumbuka, you can click here .

A statement from the Metropolitan Police said: “Police were called by security at Regent's Park at 5.15pm on Thursday to reports of an ongoing incident.

“Officers were there in support of ZSL staff at the premises.

“The incident has now concluded.”

For a recap of events as the unfolded see our live blog .