A person has been critically injured after a car and a crane crashed at a West Auckland intersection.

Emergency services were still working to free the injured person who is trapped in the car.

The crash happened shortly before 1pm on the corner of Hobsonville Rd and Brigham Creek Rd.

A Fire and Emergency NZ spokesperson told the Herald two fire engines were at the scene and were using the jaws of life to extricate the motorist, who was the car's single occupant.

It was not clear how serious the driver's injuries were.

Ruel Williams works at a car yard near where the accident happened.

"I was inside and heard a massive bang."

He went outside and saw that a large crane had crashed into a Mercedes Benz car.

He said an ambulance, fire truck and police car were at the scene, where firefighters were working on the car.

"They have got the jaws of life and are pulling the car apart. There's someone still in there."

"It doesn't look too good."

A worker in another store nearby said she had been alerted to the commotion around 1pm.

"We didn't see anything, we just heard it," she said.

"We could hear a really big crash, then the screeching of tyres."

The woman said lots of police and ambulance staff were milling around the area.

Brigham Creek Rd is currently blocked and cordons are in place. Fire crews were helping police officers divert traffic at what was usually a very busy intersection.