Scores of firefighters are tackling a blaze in the bustling Soho area of central London.

Crews were called to Dean Street at around 2pm, and about an hour later about 10 per cent of the building was alight, London Fire Brigade said.

Twelve fire engines and 60 firefighters were sent to fight the flames, which erupted in what is believed to be an office building.

Nino Ripani, manager of nearby restaurant Signor Zilli's, said: "It's really shocking, it's something that you don't see every day. It's really getting to serious stuff now - we can see the black bits coming out."

Restaurant customers who had been dining outside were brought inside but the business had stayed open, he said.

The cause of the fire is not yet known.

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