Telegram, a messaging app, has removed 78 ISIS-related conversation channels across 12 languages, the encrypted messaging service announced on Wednesday. The announcement comes amid ongoing scrutiny over app reportedly used by the Islamic State group prior to the Paris terror attacks last week.

The news came in a tweet Wednesday:

Telegram users can create group chats with up to 200 members, or open “special secret chats” where messages and photos self-destruct. The service also updated its terms of use Wednesday to include language stipulating it will block terrorism-related channels in the future. It’s a big change for Telegram, which previously said it would only abide with takedown requests regarding bots and stickers, a feature that enables users to send each other user-generated emojis.

ISIS’ use of Telegram, which  claimed 50 million international users last year, has galvanized international officials who have spent years criticizing encryption. In the days since the Paris attack, though, security experts have examined the free app and now suggest Telegram is hardly the safe haven ISIS wanted. Users are still required to sign up with their mobile phone number, for instance, and the app then stores all a users’ contacts on Telegram’s servers (a dream for intelligence analysts trying to map a suspect’s connections).

“Telegram is error prone, has wonky homebrew encryption, leaks voluminous metadata, steals the address book, and is now known as a terrorist hangout,” wrote a respected security expert known as The Grugq. “I couldn’t possibly think of a worse combination for a safe messenger.”