Hundreds of crime figures were arrested by U.S. and Australian authorities who monitored an encrypted app used by criminals to read encrypted messages, officials said Tuesday.

Australian police and the U.S. Federal Bureau of Investigation partnered together to carry out "Operation Ironside," which aims to ensnare hundreds of people suspected to be figures in organized narcotics trade across 18 countries globally.

Suspects included in the investigation were located in Australia, Asia, South America and the Middle East, the officials said.

Organized Crime Sting

Australian Prime Minister Scott Morrison said the operation was a heavy blow against organized crime across the world calling it a "watershed moment in Australian law enforcement history." 

In subsequent announcements, Australia's police department said they had arrested 224 people during the operation, including members of outlawed motorcycle groups. In New Zealand, authorities netted 35 people.

"Operation Ironside" was launched by Australian police and the FBI in 2018. Authorities in the United States promptly took control of ANOM, a messaging app famous with organized crime networks and figures in the underworld.

Officials in the U.S. distributed mobile phones with the ANOM app installed among criminals. This allowed authorities to tap into the messaging app and monitor chats about drug smuggling, money laundering and murder plots among members of drug syndicates and people with links to mafia groups.

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

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Black Market

ANOM is an app that can only be found on phones sold in the black market. These phones have been stripped of the capability to make calls or send mails. The phones could only send messages to other devices with the same app.

To get access to a hacked mobile phone, criminals had to know other criminals to get a device. In the case of the San Diego FBI agents, they were granted access by a developer who had created ANOM to compete against other encrypted communications platforms in the market.

Authorities refused to release more details about the developer, who agreed to cooperate with officers in exchange for a reduced sentence.

Law enforcement personnel have had difficulties with the prevalence of encrypted communication apps, which ANoM has conveniently solved to provide officials with more access to criminal operations, Kershaw said.

Over the course of three years, the operation involved more than 9,000 officers across 18 countries. The arrests also led to the seizure of tons of drugs and assets worth millions of dollars, officials said.

The police also acted on at least 20 "threat to kill," and potentially saved the lives of many innocent bystanders. In Sweden, officials say the operation may have prevented 10 planned murders.

The FBI is expected to present more details about the global sting on Tuesday. Kershaw noted that they are currently working on getting access to other encrypted communication apps.

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