Latest: Dubai's 86-storey torch tower engulfed by flames again

Update 6am: A fire broke out after midnight in one of the world's tallest residential towers in Dubai, engulfing part of the skyscraper and sending chunks of debris plummeting below.

More than 40 floors of the 86-storey Torch Tower were burning on one side of the building, an Associated Press journalist near the scene of the blaze said.