A propaganda video released this week by pro-ISIS hackers threatens the founders of Facebook and Twitter, which have been shutting down social media accounts affiliated with the terror group.
ISIS is known to use social media to recruit members and convey its message during attacks.
The video, posted Feb. 23 by the "Sons Caliphate Army," shows bullets riddling the photos of Facebook chief Mark Zuckerberg and Twitter CEO Jack Dorsey.
Deep-web analysts from Vocativ first spotted the video on Telegram, a social media site reported to be popular with ISIS supporters.
The amateur video claims to have hacked more than 10,000 Facebook accounts, 150 Facebook groups and 5,000 Twitter profiles, saying ISIS supporters would take over many of those accounts.
At the end of the video, the narrator addresses Zuckerberg and Dorsey directly, taunting them and warning the CEOs that ISIS supporters will hack 10 accounts for every one that Twitter and Facebook close. The video also threatens to delete the sites altogether.
Similar threats have been made before over the past year.
Twitter, the terror group's main social media platform, suspended 125,000 accounts earlier this month that allegedly threatened or promoted terrorist acts, primarily related to ISIS.
“We condemn the use of Twitter to promote terrorism and the Twitter Rules make it clear that this type of behavior, or any violent threat, is not permitted on our service,” Twitter said in a statement in early February.
Ari Mason contributed to this report.