London Balcony Collapse: Two People Killed
London Ambulance Service (LAS) initially said one man had died and another was taken to hospital.
The Metropolitan Police later said the second man had died.
The Health and Safety Executive has confirmed it is investigating the incident and inspectors had attended the scene.
Greg Hands, the Conservative MP for Chelsea and Fulham, tweeted: “Believe balcony broke when the removal men were moving a sofa out and the combined weight might have broken it.
“Casualties were removal staff. My thoughts are with their families.”
One neighbour, who asked not to be named, said the victims were Polish men in their 20s and renovations had been going on at the five-storey building for the past year.
Sky News has been told hydraulic platforms are usually used by removal firms in the area, but in this case it appears ropes were employed.
The iron railing of the first-floor balcony appears to have given way crashing 10 metres (33ft) to the ground.
The street, where the average property is worth £3.2m, was cordoned off by police.
Sinclair Johnston, an engineer who has worked on another property in the square, said the decorative railings such as the one which collapsed cannot be depended upon to support weight.
He said: “These sort of constructions are always very fragile and the iron railings can rust and the stone can become fragile and break up so you never really know how strong they are.
“It’s OK in an ordinary way but if you put any pressure on them, if you lean on them, there’s no way of knowing – you can’t depend on them.
“The ironwork is incredibly heavy so if it falls off it can be a disaster.
“The buildings were built around 1890 and I should think the railings are original or have been there for a very long time.”
Richard Scrivener, from London Fire Brigade, said: “When we arrived we made the scene safe, securing parts of the iron balcony that had broken away in the fall.
“Crews assisted London Ambulance Service to provide first aid to those injured in the fall as well as to a number of onlookers who were suffering from shock.”
A police spokesman said: “Two people are confirmed to have died, one at the scene and one in hospital.”
“Six patients were treated for minor injuries but did not go to hospital.”