The London Fire Brigade says a rescue operation is underway after a 20-meter (65-foot) crane collapsed onto a block of apartments under development and two houses.
Assistant Commissioner Graham Ellis said search-and-rescue crews were using specialized equipment to search the properties in east London as part of "a complex rescue operation" on Wednesday afternoon.
The London Ambulance Service said crews and a team of specialist paramedics who work in hazardous environments were at the scene in the Bow neighborhood.