Public help NSW cop in alleged attack

Bystanders rushed to help a NSW police officer as he tried to fight off a man who was allegedly trying to choke him.

It's alleged the scuffle began after the man walked up to the highway patrol officer's car in a street in Nowra, on the state's south coast, on Thursday afternoon.

Police say the man began punching the officer's car window several times before reaching in and grabbing the senior constable around the neck as he tried to get out.

Several members of the public rushed to help the officer before more police arrived at the scene.

The 40-year-old man was arrested and it's expected he'll be charged over the incident, police said.

The officer was not seriously injured and resumed his duties soon after the alleged attack.