newy.com.au – A bushwalker has been rescued by police helicopter after spending the night lost in Olney State Forest, west of Morisset.

The 52-year-old man was found on Wednesday morning after an extensive search involving police and volunteer emergency services.

Police were told he had become separated from a family member while bushwalking on Tuesday night and failed to return to The Basin Campground.

Emergency services were called about 4.40am on Wednesday, August 5, and a command post was established at the campground, about 24 kilometres west of Morisset.

Hunter Valley Police District coordinated a land and air search with assistance from PolAir, Police Rescue, NSW SES, NSW Ambulance, NSW Rural Fire Service and VRA Rescue NSW.

PolAir located the missing man about 10.25am, almost six hours after emergency services were alerted.

The bushwalker was winched into the police aircraft and flown to George Downes Drive at Bucketty, where NSW Ambulance paramedics assessed him.

He was treated for mild hypothermia, dehydration and abrasions before being taken to Gosford Hospital for further assessment.