Internet service monitoring sites showed more than 1,500 complaints about Signal, mostly from users in Moscow and St Petersburg. Users reported, however, that it was working normally when accessed via a VPN or used in the built-in censorship bypass mode.
“This indicates precisely a blocking of the messenger in Russia and not a technical problem on the Signal side,” Mikhail Klimarev, author of the Telegram channel “For Telecom”, told Reuters.
Signal did not immediately reply to a request for comment. Russian internet watchdog Roskomnadzor also did not immediately respond to a request for comment.
It was also impossible to register a new account on Signal without a VPN, three people from Moscow and the Krasnodar region told Reuters. When entering a mobile number, the service displayed the message “Server Error”.
Klimarev said it would be the first attempt to block the messenger in Russia.