The Iranian monthly Peivast is reporting that Iran has blocked the private encrypted messaging application Signal, ordering mobile operators to filter it from their networks.
The report comes after the Open Observatory of Network Interference (OONI) said on Twitter earlier on January 25 that "Iran seems to have started blocking" the application.
The move follows the January 14 removal of Signal from local application stores after it was reportedly deemed "criminal content" by the Islamic republic's filtering committee.
The authorities have not publicly commented on the decision to ban Signal.
Many Iranians had reportedly migrated to Signal in recent days following an update by WhatsApp of its privacy policy reserving the right to share user data with its parent company Facebook.
In 2019, Iran blocked Telegram, used by half of the country's 81 million people, claiming it endangered national security.
Iran filters tens of thousands of websites, including news sites and social media. Iranians access banned sites by using anti-filtering tools.