Officials in Pakistan have ordered that all communications flowing through BlackBerry's secure Blackberry Enterprise Server (BES) must be shut down by 1 December.
Pakistan's Ministry of Interior issued a notice to the Pakistan Telecommunication Authority (PTA) citing "security concerns" as the reason for the decision.
The BlackBerry service largely handles corporate information, securing and encrypting emails, messages and browser activity, and its closure will affect 4,000 to 5,000 people in the country.
"The PTA has issued directions to local mobile phone operators to close BES from 30 November on security reasons," a PTA spokesperson told Reuters.
"There was a challenge that the BlackBerry email service could not be tracked or decoded, which leads to the security reasons."
BlackBerry told V3 that the company provides a secure communications platform to government, military and enterprise customers.
"Protecting that security is paramount to our mission. While we recognise the need to cooperate with lawful government investigative requests of criminal activity, we have never permitted wholesale access to our BES servers," said a spokesperson.
The company confirmed that BlackBerry Internet Services will not be affected by the BES block.
The crackdown on privacy comes as Privacy International released a report claiming that Pakistani intelligence agencies sought dramatically to increase their domestic surveillance capabilities.
Pakistan's Inter-Services Intelligence (ISI) has made moves to capture mobile communications data, including over Wi-Fi, all broadband internet traffic and any data transmitted over 3G networks, according to the report.
"The ISI also requested that technology firms bidding to provide the covert system provide a 'seamless' solution, and that interception 'must not be detectable or visible to the subscriber'," the privacy group said.
"The ISI explicitly requested the system to be scalable to meet future expansion plans of the network operators it sought to tap."
Meanwhile, Eric King, deputy director of Privacy International, said that this form of surveillance breaks the human right to privacy.
"The scope and scale of the programme that the ISI wanted to build in 2013, which would monitor the entire scope of IP-bound communications passing in and through Pakistan, is neither necessary nor proportionate," he said following the release of the report.
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