Police officer hurt at large Sydney party

A police officer has been hit in the head while trying to break up a party in Sydney's southwest.

He was injured while trying to disperse a pack of about 50 people standing on a Macquarie Fields street after leaving a party late on Saturday night.

He suffered a laceration to his head and was taken to hospital for stitches.

Two men and a 16-year-old boy were arrested after the skirmish.

The men, both aged 20, were charged with offences including resisting arrest and bailed to appear in court later this month.

The 16-year-old was released into the care of an adult while investigations continue.