Stormy seas pushed a coal freighter with at least 21 Filipino crew onto a sand bank off Australia's east coast Friday, triggering a major rescue operation and warnings of a potential disaster if the ship's fuel leaks.

Officials feared that other freighters waiting off the port of Newcastle could also run aground as an 26-foot storm swell and winds of up to 50 mph battered Australia's eastern shores.

The 820-foot-long Pasha Bulker had been preparing to collect coal from Newcastle later this month. The storm surge ripped the ship from its moorings and pushed it into a sand bank early Friday, New South Wales state police said in a statement.

One by one, rescue helicopters airlifted the crew of the 40,000 ton Pasha Bulker to safety at a nearby park, where paramedics examined them and said they were in good health.

The ship was not carrying any cargo and no one was injured in the incident, but officials said there was some risk of the ship breaking apart, and leaking hundreds of tons of fuel oil and diesel into the sea.

"A response is being coordinated, and contingencies for pollution are being put in place," said New South Wales maritime chief Chris Oxenbould.

Some warned of a potential ecological nightmare.

"We can see a massive disaster here. With the significant tonnage of diesel fuel and fuel oil on board, we could see the entire coastline in that region blanketed with black, tarry slick that will have a huge impact on the environment in the area," said Ian Cohen, a lawmaker with the minority Greens party.

The state's transport minister, Joe Tripodi, said three other coal ships had sent distress calls and were at risk of foundering, with waves up to 55 feet high measured in the area.

"Obviously, their concern is that they'll be washed up," he told the Australian Broadcasting Corp.

The three distressed vessels were among 54 ships waiting outside Newcastle to pick up stores of coal bound for power stations in Japan, South Korea, Taiwan and elsewhere in Asia.

The port city is one of Australia's largest coal export centers, but loading delays have left long queues of vessels — sometimes more than 70 ships — waiting offshore.

Forecasters at the Bureau of Meteorology have warned weather conditions in the area could worsen.