LONDON (AP) — The Latest on a fire at London's Mandarin Hotel (all times local):

5:05 p.m.

The volume of black smoke billowing from a fire at London's Mandarin Oriental has gone down significantly after about an hour.

The London Fire Brigade dispatched 15 fire engines and 97 firefighters to respond to the blaze at the 12-story luxury hotel on Wednesday afternoon in the city's ritzy Knightsbridge area.

The cause of the fire is not yet known. There were no immediate reports of injuries.

The hotel says: "As the situation is still unfolding, we have no further details to share at this time, but will provide an update soon."

The thick plumes from the fire could be seen for miles earlier.

4:40 p.m.

London Fire Brigade says about 100 firefighters are tackling a blaze at a luxury hotel.

Video footage shows smoke billowing from the roof of the Mandarin Oriental Hotel in London's ritzy Knightsbridge area.

The fire brigade says it was called just before 4 p.m. (1500 GMT) to the 12-story hotel. It says 15 fire engines and 97 firefighters are at the scene.

Smoke from the fire can be seen for miles. The major road in front of the hotel has been closed, causing rush-hour traffic chaos in that part of London.

The cause of the fire is not yet known.