Plane crashes into river in Sydney

A light plane has crashed into a river in a national park south-west of Sydney.

Two people have walked away from the crash without injury.

The pilot has told 9NEWS the aircraft suffered engine failure and he was forced to ditch it.

The plane went down in Nattai National Park, near Camden.

He said he began experiencing mechanical problems while at about 3,500 feet over a nearby mountain range.

"We had a complete engine failure without warning and put it down in the swamp," he told 9NEWS.

The plane appeared to have broken in two upon impact, before it was partially submerged in the creek.

The pair was winched out of the dense bushland by a NSW Ambulance helicopter.

The rescue helicopter took them to Bankstown airport, where they were assessed by a doctor.

The aircraft was as a Jabiru J160-D, a light two-seater hobbyist aircraft.