Telegram — a popular, encrypted communication app — is at risk of being banned in Russia by the government because the app makers refused to comply with the country’s new data protection laws.

The message app, made in Russia, declined to provide the Russian government with information from its platform. In response to the decision, Alexander Zharov, the head of Russian communications regulator Roskomnadzor, warned the service may be blocked.

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At the heart of the dispute is the Russian Personal Data law, first passed in September 2015. The law asks foreign technology firms to store the personal data of Russian citizens within the country, preventing data from Russian users from leaving Russian territory.

The law, originally presented as a way to prevent foreign governments from spying on the information of Russian citizens, underwent modifications at the start of 2017 that not only required tech firms to store up to six months of personal data of Russian citizens, but also obliged the companies to provide law enforcement access to that retained data.

Telegram, an app built to provide its users with a private means of communication by allowing them to send encrypted messages to and from one another, has thus far refused to comply with the law and with requests from Russian authorities to surrender data.

Russian officials reportedly approached Telegram after it was discovered terrorists who killed 15 people in St. Petersburg in April were communicating through Telegram. Russian intelligence requested access to those users’ communications and the crypto keys that protect the conversations as part of their investigation — a request Telegram refused.

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“There is one demand, and it is simple: to fill in a form with information on the company that controls Telegram ... and to officially send it to Roskomnadzor to include this data in the registry of organizers of dissemination of information,” Zharov wrote in a social media post. “In case of refusal … Telegram shall be blocked in Russia until we receive the needed information.”

In response to the potential ban, Telegram founder Pavel Durov noted in a post on social media that his company’s service is not blocked in any other country. He said if Telegram is banned by the Russian government, then the app will continue operation elsewhere — taking any data belonging to Russian officials using the app with it.

"As soon as Telegram is blocked, the correspondence of the Russian officials, their communication with friends and relatives as well as other sensitive data via WhatsApp/Viber will move to America-controlled clouds Apple iCloud/Google Drive," he wrote.

Telegram currently counts about 6 million active users in Russia and more than 100 million users worldwide — more than social media services like Twitter and Pinterest and on pace with Snapchat. The service reports it delivers more than 15 billion messages each day.

The app’s popularity and accessibility have made it a communication tool of choice not just for average citizens concerned about their privacy but for terrorists who want to evade detection. A report published by the Middle East Media Research Institute called it the “app of choice” for a number of groups with ties to the Islamic State.