Diners were forced to flee a fire caused by Christmas decorations at a Latin American restaurant in London’s West End on Friday night.

Video footage of the blaze showed people rushing to escape MNKY HSE in Dover Street, Mayfair, after the flames spread quickly. Two people were treated by ambulance staff for their injuries.

London fire brigade said it attended the incident after being called out at 9.40pm to a fire in the basement of the building and that it was under control in less than half an hour.

The flames reportedly spread rapidly – taking hold “within seven seconds”, according to one of the guests – prompting people to run from the building.

Footage on social media showed the fire raging as revellers escaped, with some people still holding their drinks and others ducking beneath the fire to get to a door due to a ceiling decoration catching alight.

Some could be seen falling over, while others screamed and shouted at other guests to “go”.

A spokesperson for London fire brigade said: “Firefighters were called to a fire at a restaurant on Dover Street in Mayfair.

“Christmas decorations inside the building were alight and had been extinguished before firefighters arrived. About 300 people were evacuated by on-site staff and crews carried out a systematic search of the property to ensure no one was inside on arrival.

“A man and a woman were treated on scene by London ambulance service crews. Dover Street was closed while crews worked to make the scene safe.

“The brigade was called at 9.40m and the incident was over for firefighters by 10.18pm. Five fire engines and around 35 firefighters from Soho, Lambeth, Kensington and Chelsea fire stations attended the scene.”

They added that the cause of the fire remains under investigation and said thermal imaging was used to check everything was in order once the fire was put out.

About 300 people were inside the restaurant at the time, with the incident happening during its busiest time of the year. Guests were evacuated by security staff.

Despite the ferocity of the blaze, social media users commented on the calm way people made their way out of the restaurant. One person highlighted how people just “casually walked out” and another asked: “Why do they look so calm?”

Another tweeted: “Amazing how no one left their drinks behind.”