An off-duty Sydney police officer has been charged over a crash at Lake Macquarie last month.

Around 9.30am on July 18, emergency services were called to Wyee Road at Wyee, after reports a Jeep and a Hyundai Santa Fe collided head-on.

The Jeep driver, a 37-year-old man, was trapped for an hour before being released.

The Hyundai driver, a 48-year-old woman, had serious leg and internal injuries.

Her passenger, a 13-year-old boy, suffered a broken wrist.

They were all treated at the scene before being taken to John Hunter Hospital.

Officers from the Crash Investigation Unit commenced an investigation into the circumstances surrounding the crash.

Following a police investigation, the senior constable was today charged with a string of offences including aggravated dangerous driving occasioning grievous bodily harm, speeding and negligent driving.

He’s due to appear at Toronto Local Court on October 6.