Hong Kong police said Sunday they have made the southern Chinese territory's largest ever cocaine bust, seizing more than half a tonne of the drug, worth around $77 million.

Authorities said drugs officers raided separate locations over the weekend, including a warehouse in the city's suburbs, finding a total of 567 kilograms (1,250 pounds) of cocaine.

Eight people were arrested, police said, ranging in age from 24 to 55.

Those arrested included an American man, a Colombian woman with Hong Kong residency and five Mexicans, a police spokeswoman said.

"The cocaine could have come into Hong Kong by land or sea, but we're still trying to find out which way it came in," a narcotics bureau officer told the South China Morning Post.

In March, a man was sentenced to 22 years in prison over the city's biggest ever cocaine bust at the time, in which drugs weighing 372 kilograms and worth about $43 million were found.