Australian rescue workers from Sydney found a puzzling scene Friday on a catamaran spotted drifting off the Great Barrier Reef: sails up, engines running and food on the table, but no crew.

Officials launched a search for the three men missing from the Kaz II, which rescuers have already dubbed "the ghost yacht." Nine planes and two helicopters were flying over an area about 700 nautical miles long, along with four volunteer rescue boats, police and maritime officials said.

'It was a bit strange.'—Jon Hall, Queensland Emergency Management

Marine police were also towing the vessel back to shore for further investigation.

A coastal patrol aircraft spotted the vessel on Wednesday but rescue workers only confirmed there was no one aboard when they reached the boat early Friday.

The catamaran's sails were up, but the headsail was "shredded," according to Warwick Bracken of the Australian Maritime Safety Authority.

There was no indication of any other damage.

"They got on board and said the engine was running, the computers were running, there was a laptop set up on the table which was running, the radio was working … and there was food and utensils set on the table ready to eat, but no sign of the crew," said Jon Hall, a spokesman for Queensland state's Emergency Management Office.

"It was a bit strange," he said.

The vessel's emergency beacon and three life jackets were still on board, along with a dinghy.

The crew — Australians aged 56, 63 and 69 — had set out Sunday, planning to sail around northern Australia to Western Australia state, according to Sharon Davidson of the Australian Maritime Safety Authority.

Greg Connor, a forecaster with the Bureau of Meteorology, said the sailors would have faced moderate southeasterly winds of about 35 km/hr, typical weather for this time of year.

"It would have been excellent sailing conditions," he said.

"There's no reason to believe this is a weather related incident."