Search underway for boaters feared missing after crash on the Gold Coast

Two men have been seriously injured and another two are feared missing after a boat crash on the Gold Coast Broadwater early this morning.

A member of the public phoned police about 4.45am after seeing an unmanned boat in Runaway Bay.

Two men were rescued and police are searching for two other people who may be missing in treacherous weather conditions.

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The tinnie hit a port marker in the Broadwater, throwing one man overboard.

He managed to swim to Runaway Bay, while another man remained on board, caught between the steering console and the seat.

The boat spun out of control, where it hit a nearby catamaran.

The tinnie was then towed to shore and the man onboard taken to hospital.

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Water police are on the water searching for other people that they believe are unaccounted for.

A major marine search is under way with concerns two other men may have been thrown overboard.

Senior Sergeant Peter Venz from Gold Coast Water Police said investigators had received "conflicting versions" of events.

"The gentleman I was speaking to on the scene said there were four people on the vessel," he said.

"And the person who was ejected into the water stated that there were two men in the vessel.

"We have detectives up at the hospital trying to clarify whether we're still looking for two people in the water."

One man is currently in an induced coma and the other is being treated for serious injuries.