Law enforcement agencies announced on Tuesday that they have taken down yet another encrypted messaging service used by criminals, but not before spying on its users. 

Europol said police and other agencies in France, Germany, Netherlands, Italy, Lithuania and Spain have targeted a service named Matrix, whose existence came to light during an investigation into the murder of a Dutch journalist in 2021 — the app was found on a phone belonging to the man convicted for the murder.

Matrix (aka Mactrix, Totalsec, Q-safe and X-quantum) promised end-to-end encryption for a price ranging between €1,300 and €1,600, which included a phone and a six-month subscription. However, only users who received an invitation were able to sign up for the service.

Authorities identified over 40 servers across Europe, with some important systems located in France and Germany. Law enforcement managed to hack the chat service and intercept messages sent by users in real time over a period of three months. 

Investigators found that the service had at least 8,000 users around the world, who wrote messages in 33 languages. Law enforcement intercepted 2.3 million messages, mostly related to drug and arms trafficking and money laundering. 

The service was taken down on December 3, when police in France, Spain, and Lithuania arrested a few suspects and conducted searches. 

The criminals using the service were informed about law enforcement intercepting their messages through a page displayed on their phones on the same day.

Over the past few years, law enforcement has targeted several encrypted messaging services — including EncroChat, Ghost and Sky ECC — in many cases spying on their users before shutting them down. In the case of a service called ANOM, the FBI itself distributed encrypted phones to criminal syndicates across 100 countries and then monitored their communications. 

Europol noted that Matrix used a technically more complex infrastructure compared to previous services such as EncroChat and Sky ECC.

Authorities announced last year that a three-year investigation conducted following the takedown of EncroChat resulted in 6,500 arrests worldwide and the seizure of hundreds of tons of drugs.

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