The San Francisco company has recently shut down at least 2,000 accounts linked to ISIS and its supporters and Twitter is now investigating.
At Twitter headquarters, security officers were on alert throughout the day, but no one talked about the threats.
A spokesman released a statement through email saying, “Our security team is investigating the veracity of these threats with relevant law enforcement officials.”
For security professionals, this is a possible threat that has to be carefully balanced. “I think the FBI has to determine whether the veracity of the threat and whether it comes from ISIS itself or is it a message to followers to do something. That’s the key,” former FBI agent and private investigator Rick Smith said.
Smith doubts that ISIS has sent or can send anyone to San Francisco immediately to carry out these threats.
However, there is the possibility of a lone wolf trying to mount an attack, so Twitter will have to tighten security at their downtown San Francisco offices.
The threats against Twitter CEO Jack Dorsey were posted online Sunday on a website called, JustPasteIt.
“Though this threat seems legitimate, it was posted to a site that anyone could have posted to and the reality is it could have been a 12 year old in Wisconsin, we don’t know if it’s a real terrorist or it’s someone making a joke,” Sher said.
Social media has become their primary tool for recruiting followers and encouraging independent attacks.