Groups are also not fully encrypted, end-to-end. This includes private groups. Private groups cannot be seen by other Telegram users, but Telegram itself can see the groups and all of the communications that you have in them. All of the same risks and warnings about channels can be applied to groups. For example, WhatsApp restricted the number of times a user could forward something, and developed automated systems that detect and flag objectionable content. It is unclear who runs the account, although Russia's official Ministry of Foreign Affairs Twitter account promoted the Telegram channel on Saturday and claimed it was operated by "a group of experts & journalists." But because group chats and the channel features are not end-to-end encrypted, Galperin said user privacy is potentially under threat. Perpetrators of such fraud use various marketing techniques to attract subscribers on their social media channels.
from cn