A cruise ship named Coral Adventurer ran aground on a reef off the north coast of Papua New Guinea on Saturday morning. It remains stuck about 30 km from Lae, PNG's second-largest city. Authorities have “detained” the ship, worried it might be unsafe to sail due to possible damage. The ship carries 80 passengers and 43 crew members. Luckily, no one was hurt. The passengers were scheduled to return to Australia by a chartered flight from Cairns on Tuesday. Both Papua New Guinea and Australia have started investigations into how the grounding occurred. Samson Kua, PNG’s acting police commissioner, said the detention order forces the ship to stay in PNG waters until all formal procedures are cleared. The National Maritime Safety Authority of PNG will give a clearance letter once the ship is safe to leave. The Australian Maritime Safety Authority (AMSA) also said they detained the Coral Adventurer under the Navigation Act 2012. They suspect the ship is “not seaworthy due to potential damage” from the reef. AMSA highlighted possible failures in following safety management rules. AMSA is working with Coral Adventurer’s operator, the ship’s classification society, and PNG’s maritime authority. Coral Expeditions, the company running the ship, told the media initial checks show no damage. They said detailed inspections of the hull and surrounding marine environment will happen once the ship is refloated. The Australian Transport Safety Bureau (ATSB) has also begun an investigation. They do not know the full extent of hull damage but report no water intrusion so far. ATSB expects a preliminary report in about two months, unless a serious safety issue is found sooner. Coral Expeditions cancelled the remaining tour for passengers on Monday. A tugboat was sent on Sunday to help free the ship. More refloating attempts are scheduled for Tuesday. Notably, the Coral Adventurer was already under investigation after a separate incident in October. An 80-year-old passenger, Suzanne Rees from Sydney, died after allegedly being left behind on an excursion on Lizard Island. She was found dead after a search.