Australian police have seized a record 2.3 tonnes of cocaine and arrested 13 people in raids after the suspects’ boat broke down off the coast of Queensland, authorities said.

The drugs had a sale value of 760 million Australian dollars (£388 million) and equalled as many as 11.7 million street deals if they had reached the country of 28 million people, federal police claimed.

Investigators told reporters in Brisbane that the drugs were transported from an unidentified South American country.

The arrests on Saturday and Sunday followed a month-long investigation after a tip-off that the Comancheros motorcycle gang was planning a multi-tonne smuggling operation, Australian Federal Police Commander Stephen Jay said.

The smugglers made two attempts to transport the drugs to Australia by sea from a mothership floating hundreds of miles offshore, Mr Jay said.

Their first boat broke down, and the second vessel foundered on Saturday, leaving the suspects stranded at sea for several hours until police raided the fishing boat and seized the drugs, he said.

The mothership was in international waters and was not apprehended, Mr Jay said.

Authorities have seized more than one tonne of cocaine before, Mr Jay said, but the weekend’s haul was the biggest ever recorded in Australia.

Those charged are accused of conspiring to import the drug into Australia by sea and were due to appear in various courts on Monday. The maximum penalty under the charge is life in prison.

Some were arrested on the boat while others were waiting on shore to collect the cocaine, police said. Two were under age 18 and all were Australian citizens, they said.

“Australia is a very attractive market for organised criminal groups to send drugs such as cocaine,” Mr Jay said.