A 20-metre long crane fell on two houses in east London on Wednesday afternoon, killing one woman and injuring four other people.
The woman was found on the first floor of one of the houses that was hit in Bow, east London.
Photos from the scene showed a crane leaning on the houses and significant damage to the rooftops.
The crane also fell on flats that was being constructed, according to London's Fire Brigade.
Among the four people who were injured, two were brought to the hospital with head injuries.
"We treated four people at the scene. We treated two of these patients for head injuries and took them to hospital and we assessed the other two patients at the scene," a spokesperson for London's Ambulance Service said in a statement.
"This is a tragedy. My heartfelt condolences go out to the family of the victim who died during this incident in Bow today," said London Mayor Sadiq Khan on Twitter.
"I sincerely hope that the four individuals injured make a full recovery. We must ensure the lessons are learned so an accident like this never happens again."
The Fire Brigade received the call at 2:39 pm BST (3:39 pm CET).
Medics received a call about the incident at 2:42 pm BST (3:42pm CET) and arrived at the scene within three minutes, said a spokesperson for London's Ambulance Service.
Eyewitness Bridget Teirney, who posted video footage of the incident to Twitter, said it looked like one man was crushed under the crane, but he eventually was treated by the ambulance.