Australian authorities said Thursday that they had identified the ship that allegedly spilled up to 15 tons of oil in the Great Barrier Reef a year ago. The foreign ship, whose name and country of origin has not been revealed, now faces prosecution for the spill that is estimated to have cost about $1.5 million to clean up — a cost that the Australian government would now seek to recoup.

“The challenge was then to track down the individual ships, many of which were on international voyages, check onboard records, interview crews and take oil samples for elimination testing against samples from the spill,” Queensland Ports Minister Mark Bailey reportedly said. “It was a difficult investigation as the ship believed to be responsible is foreign registered with a crew of foreign nationals.”

Bailey said that details of the foreign-registered vessel, along with all the evidence, have been forwarded to the commonwealth director of public prosecutions, which will decide whether the ship’s operators will be prosecuted.

“This is an extremely complex legal process involving both Australian and international maritime law and we don’t want to jeopardize the case by identifying the suspect vessel while the evidence is being fully considered,” Bailey said.

According to ABC News, the spill could attract a maximum fine of almost $30 million, including nearly $12 million under Queensland law and $17 million under Commonwealth law.

The Great Barrier Reef, one of the world’s most fragile and diverse biodiversity hotspots, is already reeling under its worst coral bleaching on record, with up to 93 percent of the reef suffering from some level of damage. The reef stretches over 1,400 miles along Australia’s northeast coast and serves as a habitat for nearly 100 species of jellyfish, 3,000 varieties of mollusks, 1,600 types of fish, over 130 varieties of sharks and rays, and more than 30 species of whales and dolphins.

Luckily, the oil spill, which took over two weeks to clean up, affected only a small number of animals in the region — including two seabirds that died. 

“We will ensure Queenslanders are not out of pocket for this incident and will seek full cost recovery through the Australian Maritime Safety Authority either out of the offending ship’s insurance or from a national plan fund set aside for these occurrences,” Bailey said.