Michael Gavin saw the accident while he was standing at Vauxhall station.
I was facing the building when it happened and I heard a loud bang. The top of the crane was actually obscured by fog so I didn't see the impact.
But I heard a bang and saw the body of the helicopter falling to the ground along with pieces of the crane and then a large plume of smoke afterwards.
More top news
Speaking at Glastonbury Festival, the shadow chancellor said people who died in the Grenfell fire were "murdered by political decisions".
It's the largest Eid event in Europe, and today's figure smashed last year's record 88,000 people in attendance.
Cloudier to the south with light and patchy rain at times.