Islamic State has released a video in which it claims to have hacked thousands of Facebook and Twitter accounts in response to the two companies having suspended the accounts of supporters of the extremist group.
The 25-minute video, posted on an Islamic State channel on the encrypted messaging service Telegram, also makes direct threats against Facebook chief Mark Zuckerberg and Twitter chief Jack Dorsey.
Both Facebook and Twitter have taken action in recent months to shut down accounts used by IS supporters to push out propaganda, with Twitter announcing it had suspended 125,000 accounts with alleged links to the extremist group since mid-2015.
The video was uploaded by a cell called Sons of the Caliphate Army, which emerged after British IS operative and hacker Junaid Hussain was killed by a US drone strike last year.
It's claimed in the video that 10,000 Facebook accounts and 5000 Twitter accounts, as well as 150 Facebook groups, had been hacked with many turned over to IS supporters.
The following typed message appears in the video: "To Mark and Jack, founders of Twitter and Facebook and to their Crusader government, you announce daily that you suspended many of our accounts and to you we say: Is that all you can do?"
"If you close down one account, we will take 10 in return and soon your names will be erased..."
The video purports to show hackers changing the profiles of accounts, while also uploading IS propaganda to the accounts.
At one point, photographs of Zuckerberg and Dorsey appear on the screen, followed by a barrage of bullets.
It also features tributes to martyrs and footage of a series of suicide attacks using vehicle-born improvised explosive devices.
