10 people have been evacuated from a building in Sydney’s lower North Shore after the back wall collapsed.

The office building on Alexander Street in Crows Nest is adjacent to a building site, but the cause of the collapse is not yet known.

Firefighters are on the scene, but luckily no-one has been injured.

One occupant, Helen, was treating a patient when the collapse began. After evacuating, she documented the collapse in photos.

She described to Jim Wilson how the walls shook as a crack grew at the back of her office.

“I heard the cracking of the wall, and next thing I can see my wall is separating from my internal wall.

“It was quite scary … I looked at the wall and said ‘Oh my God, is that my eye[s] or something else?”

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