The police and Public Prosecutor now have access to the contents of 3.6 million messages sent through a network of specially customized BlackBerry smartphones. The authorities believe that these messages were sent by criminals, the Prosecutor announced on Thursday.

In April 2016 the network of Nijmegen business Ennetcom was taken off the air. According to the Public Prosecutor, a criminal investigation into Ennetcom was launched after the technology company surfaced in a number of investigations into assassinations.

Initially the polcie thought that some 19 thousand people used the Ennetcom network to send encrypted messages. On Thursday the Public Prosecutor spoke of 40 thousand active users.

In September a judge gave the Dutch police permission to access Ennetcom's Canadian servers. Working with the Netherlands Forensic Institute, the police managed to break into and decrypt 7 terabytes worth of messages. 

The Prosecutor hopes that evidence can be extracted from the now decrypted messages in matters relating to "assassinations, armed robbery, drug trafficking, money laundering, attempted murder and other organized crime."

According to the prosecutor, the necessary encryption keys "fell into the hands of prosecutor and police". A spokesperson would not tell NU.nl exactly how that happened. He did stress however, that the PGP - the security standard used - was not broken.