According to US authorities, one of the primary reasons for Telegram’s popularity among terror groups is the escalated measures recently adopted by its rival social media platforms. Twitter and Facebook have cracked down on extremist content. Earlier in the year, Twitter suspended over 235,000 accounts for promoting violence and terrorism.

“Positive steps by Twitter, for example, are part of the reason Telegram is becoming the new thing,” said an unnamed senior US official, involved in monitoring Isis’ online presence.

“It’s alarming because it shows they’re really good at adapting to new means,” the official said. Highlighting the challenges faced by authorities tasked with preventing attacks, he pointed out that one of the ways to stop attacks involved collaboration between private companies and government officials. Both parties must “figure out how to deny them these capabilities before they even start using them”, he said, adding, “That simply hasn’t been the case with Telegram.”

According to MEMRI researchers, Telegram also provides a meeting ground for “not that smart” wannabe jihadists and experts, who in turn recruit and groom the naive but willing to becoming potential martyrs, putting deadly plans into action.

“The West has been generally two steps behind the jihadis when it comes to cyber,” Stalinsky said. “Many people in government are still focused on Twitter, and they need to be. But what we tell them is, ‘That’s no longer the main story.’ ”