UPDATE: The Bundaberg RACQ LifeFlight Rescue helicopter has returned to base after searching part of the Wide Bay coastline for a diver who has been missing since Saturday morning.

The skipper reported the man, aged in his thirties, missing after he failed to resurface.

The Queensland Police Service (QPS) first sent the helicopter to the search area on Sunday.

Over the past four days, the crew have spent almost 15 hours searching for the diver from above.

Lifeflight chopper returns to base : The Lifeflight chopper returns to base following its search.
Lifeflight chopper returns to base : The Lifeflight chopper returns to base following its search.

EARLIER: Police have scaled back the search for a missing free diver last seen after failing to return to a six-metre vessel off Elliott Heads.

The 38-year-old man from Bundaberg was with friends when he didn't resurface just after 8am Saturday.

After a five-day sea, land and air search, involving multiple agencies, spanning hundreds of nautical miles, there has been no sign of him since.

Initial inquiries suggest he may have suffered a medical event.

Local police officers and surf lifesaving will continue patrols along the shore between Burnett Heads and Innes Park.

The man's family has been notified and police would like to thank the community and other services for their assistance.

If you have information for police, contact Policelink on 131 444.

Earlier, a spokeswoman for Lifeflight said the Lifeflight chopper was still carrying out its search this morning.