Vietnamese authorities have detained the captain of the speedboat that capsized off the coast of southern Vietnam, killing 15 Indian tourists, as investigators examine possible violations of inland waterway transport safety rules.

The vessel, carrying 32 Indian tourists and four Vietnamese crew members, overturned on Saturday afternoon, shortly after departing Hon May Rut Ngoai island near Phu Quoc, less than 500 metres from the shore.

According to the Indian Embassy in Hanoi, 16 survivors have been discharged from the hospital and are expected to return to India, while one passenger continues to receive treatment in critical condition at a Vietnamese hospital.

Officials are also arranging the repatriation of the victims. The bodies are being transported to Ho Chi Minh City before being flown back to India after the completion of necessary legal and administrative formalities.