CANBERRA/AMSTERDAM • Global law enforcement agencies hacked into an app used by criminals and read millions of encrypted messages, leading to hundreds of arrests of organised crime figures in 18 countries, officials said yesterday.

The operation by Australian and European police and the US Federal Bureau of Investigation (FBI) ensnared suspects in Australia, Asia, Europe, South America and the Middle East involved in the global narcotics trade, they said.

More than 800 suspected members of organised crime gangs were arrested and US$148 million (S$196 million) in cash seized in raids around the world. Tonnes of drugs were also seized, the officials said. Named Operation Trojan Shield by the FBI, it was one of the biggest infiltrations and takeovers of a specialised encrypted network.

Australian Prime Minister Scott Morrison said the operation "struck a heavy blow against organised crime - not just in this country, but one that will echo... around the world". He told reporters in Sydney: "This is a watershed moment in Australian law enforcement history."

Australian Federal Police Commissioner Reece Kershaw said police there had arrested 224 people, including members of outlawed motorcycle gangs, while New Zealand said it had detained 35 people.

In Europe, officials said 75 Swedish suspects were arrested and over 60 detained in Germany. Forty nine were arrested in Holland.

The operation was conceived by the Australian police and the FBI in 2018, under which officials in the United States took control of the An0m messaging app used by organised crime networks.

When an Australian underworld figure began distributing customised phones containing the app to his associates as a secure means to communicate, police could monitor their messages.

The gangs believed the system was secure because the phones did not have any other capabilities - no voice or camera functions were loaded - and the app was encrypted.

Criminal groups in more than 100 countries were given the phones, an FBI official said.

"We have been in the back pockets of organised crime," Mr Kershaw said at the media briefing. "All they talk about is drugs, violence, hits on each other, innocent people who are going to be murdered."

Mr Kershaw said the Australian underworld figure, who had absconded from the country, had "essentially set up his own colleagues" by distributing the phones and was a marked man.

"The sooner he hands himself in, the better for him and his family," he said.

REUTERS