Telegram, a highly encrypted messaging app used by Islamic State (IS) to spread propaganda and recruit fighters, has taken down public posts made by the terrorist group days after the Paris attacks.
The Berlin-based service, which has 62 million monthly active users, has grown in popularity because of its end-to-end encryption method which makes messaging between people ultra-secure. It means that no hackers can snoop on a conversation that is taking place via the app.
But Telegram also has a feature called "Channels" which allows a person to broadcast a message to an unlimited number of people and in public. This was being used by IS to distribute propaganda and advertisements encouraging people to donate money to the group, according to researchers at private intelligence agency Flashpoint.
As a result, Telegram said on Wednesday in a statement that it has "blocked 78 ISIS-related channels across 12 languages", adding that it was introducing an "easier way for our users to report objectionable public content in the upcoming update of Telegram this week".
But this action does not include private messages between participants, meaning that communication between IS members in single chats will not be blocked or reported.
The move comes just days after the Paris attacks which left 129 people dead and the bombing of a Russian airline over Egypt last month which killed 224. ISIS claimed responsibility for both incidents.
Telegram gained popularity in the wake of the Edward Snowden revelations about U.S. government surveillance, and it made clear in its statement that it did not want to jeopardize the principles it was founded on.
"Please note that this does not apply to local restrictions on freedom of speech. For example, if criticizing the government is illegal in a country, Telegram won't be a part of such politically motivated censorship. This goes against our founders' principles. While we do block terrorist (e.g. ISIS-related) bots (automated messages) and channels, we will not block anybody who peacefully expresses alternative opinions."
News of ISIS using Telegram was circulating as early as December. The Paris attacks appear to have ramped up pressure on Telegram to act.