29 stone primate prowled a staff corridor after he was called for dinner

The 29st gorilla who broke out of his London Zoo enclosure got through two unlocked gates before downing 12 pints of undiluted squash, it was revealed today.

Kumbuka was able to walk out of his den when his first door was left open and a second security gate was unlocked after he was called for dinner.

A zookeeper in the area scrambled to secure the gorilla as the thirsty primate gulped down a huge bottle of cordial he found.

Scroll down for video

Gorilla Kingdom reopened after being closed throughout the morning - and Kumbuka (pictured) was back in his den

Zoo keepers today patching up the gorilla enclosure at London Zoo where Kumbuka the Gorilla escaped

Professor David Field, Zoological Society of London's Zoological Director, has revealed the real events behind Kumbuka the gorilla's dramatic escape

Zoological Society of London's Zoological Director, Professor David Field, revealed the real events behind the escape in a blog post titled 'Kumbuka the Gorilla: What Actually Happened'

In the post he describes the dramatic events from the point of view of 'those who were actually there'.

He admits that there were unsecured doors, which the wily primate was able to exploit in his bid for freedom.

Staff said Kumbuka was given a chocolate chip cookie yesterday evening as a 'special treat' from his specially managed diet which consists of nuts, vegetables and fruit

Bid for freedom: The gorilla is reported to have escaped 'through an open door', and an unlocked gate before entering a staff area

Kumbuka was called in to his own private quarters, as he must east separately from the female gorillas - due to his appetite the others 'wouldn't get a look in'.

He then made an opportunistic escape from his unlocked den into the staff-only service corridor where a zookeeper was working.

The zookeeper had formed a strong bond with the huge animal, and was able to keep Kumbuka calm before setting off to get help.

Gorilla Kingdom was this morning closed to members of the public for repair work

Back on display: Gorilla Kumbuka pictured eating his lunch in front of visitors to London Zoo

Prof Field said: 'The zookeeper was able to continually reassure Kumbuka, talking to him calmly and in the same light-hearted tone he would always use, as he removed himself from the area.

The gorilla was then contained in the non-public area of the zoo.

He curiously prowled around his new surroundings, and came upon a stash of undiluted blackcurrant squash - which he promptly drank.

The zoo confirmed Kumbuka was back in his den at 6.21pm after being tranquillised.

Prof Field stressed that at no point was the large male gorilla a threat to the public.

Following the breakout Kumbuka (pictured today), spent more than an hour outside his main enclosure before keepers were able to use a tranquilliser dart

Witnesses said the gorilla launched himself at the glass (pictured) earlier on the day of his escape. But the behaviour was just 'posturing'

He explained in his post that the behaviour exhibited by Kumbuka earlier in the day of his escape was posturing on his part, which is to be expected by a father and dominant male.

Zoo curator Malcolm Fitzpatrick agreed that Kumbuka had not displayed aggression before his escape, and described him as a 'gentle giant'.

As the dominant male in the troop he sometimes behaves in a way to assert his position within the hierarchy, which are said to be 'completely natural'.

Although the species needs attentive care and can be volatile in nature, most gorilla charges occur when provoked.

There was a police presence outside London Zoo on Friday morning following the incident

Irony: This image from 2014 shows Kumbuka in his enclosure looking at a stocktake board

Then a 16-year-old silverback, the gorilla pictured playing in his den two years ago

Many said yesterday's escape with rather ironic, after these photographs re-emerged

The 'gentle giant' was soon happily back in his enclosure, and given a treat special treat after his dramatic episode.

Prof Field said: 'Kumbuka and his family are happily playing, eating and sleeping in Gorilla Kingdom.