A New South Wales police officer and volunteer firefighter involved in a car crash in Sydney’s south last week has died in hospital.

Timothy Proctor, 29, a probationary constable with the Liverpool Police Area Command, was driving on Heathcote Road at Lucas Heights, in Sydney’s south, about 2:00pm on Thursday when another car crossed to the wrong side of the road and collided with his car.

Mr Proctor was cut out of his car and taken to Liverpool Hospital in a critical condition.

After a three-day battle, he died this morning.

Dash-cam footage captured by the other driver shows the Honda Civic driving southbound in the 100kph zone before drifting to the other side on the road, clipping a Toyota Yaris and then hitting Mr Proctor’s red Honda Jazz.

The 65-year-old female driver of the Honda Civic was taken to the same hospital.

She remains in a coma in a critical condition.

NSW Police Commissioner Mick Fuller said Mr Proctor, who decided on a career in policing after quitting his job in IT, was well-respected by his colleagues.

“My thoughts are with Timothy’s wife Dianne, his family, friends and colleagues at this incredibly difficult time,” he said.

“Timothy was certainly well on the way to a wonderful policing career and was well respected by his colleagues and all who knew him.

“He joined the police force after being a volunteer firefighter and had a tremendous passion and commitment for all emergency services and the community.”

Mr Proctor’s family requested privacy.

Investigations into the crash are continuing.