A 20-metre crane collapsed onto a block of flats in the Bow area of east London on Wednesday, leaving residents trapped inside.

While there is no official confirmation, four people are believed to be injured as the London Fire Brigade (LFB) works on the “complex” operation on site with a police blockade in place.

“A 20-metre crane has collapsed on to a block of flats under development and into two terraced houses on Compton Close,” said LFB assistant commissioner Graham Ellis.

“Our urban search and rescue crews are undertaking a complex rescue operation and using specialist equipment to search the properties. This is a multi-agency response and is likely to be a protracted incident,” he said.

Images on social media show firefighters with ladders propped up against a house with its roof caved in, while aerial images show the twisted crane embedded in the building.

A number of crews and “specialist resources” are at the scene, the London Ambulance Service said on Twitter.

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