Australian police say Tongan authorities have seized more than 200kg of cocaine destined for Australia from a yacht stranded on an uninhabited atoll with a badly decomposed body on board.
Divers on a reef in the Vava'u Group, where the yacht Jereve grounded, found the body.
Tongan police say the street value of the narcotics is estimated to be up to $US120 million.
The 13m upmarket yacht left Ecuador in August, laden with 204 1kg blocks of cocaine, the ABC reports.
Australian police say contact was lost with the vessel on 5 October and it was found washed up an isolated atoll 10 nautical miles off the capital of Tonga one month later.
They say two crew members are believed to have been on board when the vessel left Ecuador.
The Australian police say the stash had been monitored from the time it left Ecuador.
Federal Assistant Commissioner for Serious and Organised Crime, David Sharpe, says they received an initial tip-off that a huge shipment was bound for Australia on the Jereve.
Tonga's police commissioner told Radio New Zealand International on Thursday bad weather had delayed efforts to search the vessel for several days.
The seizure was part of an joint operation involving the Tongan police, Cook Islands police, the Australian Federal Police, Australian Customs and Border Protections Service and the United States Drug Enforcement Administration.
Listen to Tonga's Police Superintendent Grant O'Fee