Residents in an apartment block that sits above the newly-built M4 WestConnex tunnel in Sydney’s inner-west have been evacuated after cracks appeared in the building.

Firefighters were called to Green Trees apartment complex on Knocklayde Street in Ashfield about 3.30am on Friday after the cracks appeared and movement was detected in the building.

The building is about 20 years old, but firefighters said it was too early to determine the cause. They were investigating the car park and the M4 tunnel underneath.

NSW Fire and Rescue said the cracking was localised to one corner unit in the three-storey building and a total of six units were evacuated.

“On arrival we did confirm there has been some minor movement of the building so we commenced evacuations of approximately 10 people,” said Superintendent Adam Dewberry.

“We’ve also isolated the power and other utilities for safety reasons.”

Members from WestConnex, public works engineers and the Inner West Council remained onsite investigating.

Residents on the floor were evacuated to a nearby local community centre, NSW Police Detective Acting Superintendent Despo Fitzgerald said.

“There is no fears of an imminent collapse so we are allowing them to go in and get their items and return to the evacuation centre,” she said.

Emergency services were called to the building about 3.30am on Friday. Photo: ABC

Superintendent Dewberry the emergency service call was triggered because “an occupant had trouble opening their door”.

When firefighters arrived, they found the tiles in the unit that had popped up, minor cracking in the wall and “some realignment problems with the doorway”.

“The extent is still being determined and that’ll be up to the engineers and other agencies to work out,” he said.

Superintendent Dewberry said laser measuring equipment carried to the scene were unable to detect any new movements in the building.

He said investigators and the tunnel operators have found “no link at this stage” to the cracks and the WestConnex tunnel.

“It’s very early on in the situation here and there’s a lot to be investigated and strategies to move forward,” he said.

The emergency call in the Ashfield follows two other high profile incidents involving cracks appearing in a Sydney apartment building.

The first was the Opal Tower in Sydney Olympic Park and the other was the Mascot Towers building.

Both of these cases resulted in residents pursuing lawsuits.

-ABC