A huge blaze tore across the roof of one of London's top hotels Wednesday, just days after it announced the completion of a multi-million-dollar renovation project.

More than 100 firefighters were sent to tackle the fire at the five-star Mandarin Oriental hotel, in the exclusive Knightsbridge district of the UK capital.

Plumes of thick, black smoke were seen billowing into the air above Hyde Park, as traffic in the area was brought to a standstill.

There were no immediate reports of any casualties. The hotel group said it believed that all guests had been evacuated.

First reports of the fire emerged just before 4 p.m. local time. Two hours later, the London Fire Brigade said that 120 firefighters were still working to bring the fire under control and that the fire service was likely to remain on the scene for the rest of the evening.

Roads in the area were closed while the emergency services responded to the fire and train services have been disrupted, the city’s transit authority, Transport for London, said on Twitter.

The hotel had recently been undergoing a major refurbishment of its 181 guest rooms and suites.

Knightsbridge is one of the most affluent neighborhoods in London, home to luxury stories Harvey Nichols and Harrods.

The hotel was built in 1889 and first opened as an exclusive gentleman’s club, according to the group’s website. Just ten years later, a fire damaged the top three floors of one wing and destroyed a section of the roof. It was reopened in 1902 as a luxury hotel.

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