Two men have died and six other people have been injured after part of a balcony collapsed in west London.
Railings on the balcony of a building at Cadogan Square, Knightsbridge, collapsed at about 10:00 GMT, London Ambulance Service (LAS) said.
The deceased were removal men who were moving a sofa, according to an MP.
Eight people were treated for injuries with one man dying at the scene and another dying after being taken to hospital, LAS said.
Chelsea and Fulham MP Greg Hands tweeted: "Balcony collapse in Cadogan Sq. Just spoke with Cadogan Ests [Cadogan Estates, a property company], not their property, but 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."
Sudarma Rajapaksha, who works in a neighbouring building, said: "My colleague heard the noise, the sofa had fallen down."
Raj Ramanoop, who was close to the scene when the incident happened, said: "I was down the street there - a friend said there has been an accident and then the air ambulance came down.
"Then I knew something serious had happened. I heard that it was a sofa that was either going out or going in."
A neighbour, who wanted to remain anonymous, told BBC News: "They were trying to pull a couch up to the first-floor apartment with ropes. Was apparently too heavy. The fence broke off and fell on the workmen below."
Cadogan Square is made up of residential properties, with many of the buildings divided into flats.
The first-floor balcony is believed to have been connected to property number 37, a five-storey terraced building.
The decorative wrought-iron railing appears to have fallen about 10m (33ft) to the ground although the stone base of the balcony looks undamaged.
A number of long ropes are hanging from the balcony to the ground where plastic sheets are gathered.
A police tent has been erected on the pavement below and the street has been closed to the public.
Surveying company Select Services, whose employees were working nearby but not involved in the incident, said one of its workers had witnessed the events and was subsequently treated for shock.
He has been sent home to recover by the company.
LAS said it sent three ambulance crews, an advanced paramedic, the hazardous response team and a London air ambulance to the scene.
A London Fire Brigade spokesman said: "When we arrived we made the scene safe, securing parts of the iron balcony that had broken away in the fall."
Police are in the process of identifying the dead men's next of kin while an investigation is under way to establish the circumstances.
The Health and Safety Executive and the local authority have been informed.