Islamic State (ISIS) cyber hackers are back in business after laying low for several months following the death of their cyber expert British member in a drone attack last August.
Last Sunday, ISIS published more than 54,000 Twitter accounts, including passwords, on its "Cyber Caliphate" website that was set up by ISIS member Junaid Hussain before his death some four months ago, according to the Daily Express.
"We are back,'' the group's Twitter account announced.
The ISIS cyber account reportedly encourages users to check the list of hacked accounts and use them to promote ISIS propaganda.
"Cyber victims were forced to defenselessly watch as ISIS rhetoric appeared under their names,'' said the paper.
Also posted on the social media platform are mobile phone numbers of the heads of the CIA, FBI and America's National Security Agency (NSA). The cyber report likewise stated that most of the victims are based in Saudi Arabia and some are British.
"I am horrified at how they got hold of my details,'' said a half-British engineer based in Saudi Arabia.
Hussain hailed from Birmingham and had led the ISIS computer hacking division until he was killed in August by a US drone carrying out a joint operation with Britain, the Express reported.
Since his death, the hacking group—which briefly hacked a Pentagon Twitter account earlier this year—had stayed low. But after spending months reportedly gathering data, it reappeared on Twitter last Sunday declaring they are back.
The group also taunted the West before tweeting a link to the database of stolen Twitter accounts, saying "We need years to publish what we have. We will raise our flag in the heart of Europe."
Experts have described the ISIS hacking of cyber accounts as "a dangerous escalation of the global cyber war.''
"It is very worrying that terrorists are gathering data in this way,'' stressed cyber security expert Tony McDowell.
Twitter has already suspended the account, said the report.