Australian officials have arrested the captain and chief officer of a Chinese coal ship which ran aground on the Great Barrier Reef.

The captain, 47, has been charged with liability for damage to a marine park, while his colleague, 44, was allegedly on watch when the Shen Neng 1 grounded.

Officials say the ship leaked tonnes of oil and caused extensive damaged to the fragile coral of the marine reserve.

The men face large fines and up to three years in prison if found guilty.

Environmental officials say it could take 20 years for the reef to recover.

Australia’s Federal Police said the two Chinese men, who have not been named, were arrested on board the ship and would appear in court in Gladstone on Thursday.

The bulk carrier is believed to have been taking an illegal shortcut when it ran aground on 3 April on its way to China from the port of Gladstone in Queensland.

In a statement, police said their investigations had found that the Shen Neng 1 had “failed to turn at a waypoint required by the intended course of the ship”.

Salvage crews pumped some 1,000 tonnes of fuel oil off the ship before it was refloated on Monday and towed to safe anchorage.

Officials who have inspected the surrounding area say the ship caused serious damage as it dragged along the reef.Its hull tore a gash more than 1km (0.6 mile) long in the reef and leaked oil into waters used as a breeding ground for seabirds and turtles.

There is also concern that toxic paint scraped off the hull had immediately begun killing off corals in the vicinity.

A senior scientist who surveyed the damage on Wednesday said marine life had been “completely flattened and the structure of the shoal has been pulverised by the weight of the vessel”.

‘Years to recover’

“There is more damage to this reef than I have ever seen in any previous Great Barrier Reef groundings,” said David Wachenfeld of the Great Barrier Reef Marine Park Authority.

He said by an optimistic estimate, it would take between 10 and 20 years for the reef to recover.

Small traces of fuel oil believed to have come from the ship are reported to have begun washing up in a nature sanctuary on the reef.

Experts said there was no significant threat but the oil could affect seabird and turtle breeding sites.

The Shen Neng 1 was carrying more than 950 tonnes of fuel oil and about 65,000 tonnes of coal when it ran aground 70km (43 miles) off the east coast of Great Keppel Island.