Australian police have seized 2.7 tonnes of cocaine - the country's largest ever such bust - from an underground bunker system in western Sydney.

The drugs, with an estimated street value of A$816m (£433m, €500m), were found on Friday in underground bunkers concealed beneath false floors in three shipping containers at a property in Londonderry.

Two men aged 21 and 25, who allegedly attempted to flee from police, were arrested at the scene and charged with possessing a commercial quantity of an unlawfully imported border-controlled drug.

Police say the cocaine was smuggled into Australia via the small town of Midge Point in North Queensland on the orders of an organised crime group.

The two men, who were remanded in custody after appearing in court on Saturday, face life in prison if convicted.

Police said the raid on the Londonderry property was part of "Operation Minjiang" which was launched in May after 40kg of cocaine was found floating in the water off a boat ramp at Midge Point.

Another six people in Queensland and New South Wales were arrested and charged as part of investigations sparked by the find, police said last week.

An alleged "mother vessel" suspected of being part of the smuggling operation has also been detained in Solomon Islands.

AFP Commander Stephen Jay said the alleged plot showed "how highly organised and determined these criminal networks are, and the extreme lengths they are willing to go to in pursuit of profit.

"Investigations into the origin of the drugs remain ongoing, and we will work with our international and domestic law enforcement partners to identify the criminal syndicates and anyone else involved in facilitating this alleged attempted drug import."