Boris Johnson says helicopter crash 'could have been much worse'
16 January 2013 Last updated at 16:49 GMT
Air crash investigators are trying to find why a helicopter clipped a crane in central London, leading to the deaths of a pilot and a person on the ground.
The aircraft had been flying from Redhill in Surrey to Elstree in Hertfordshire, when the pilot, Peter Barnes, was asked to divert to Battersea Heliport because of poor visibility.
Several cars and buildings caught fire as the burning wreckage plunged to the ground.
The Mayor of London, Boris Johnson, offered his condolences to the bereaved and said there would be a full investigation.
He added that the accident could have been much worse.