ISIS Tweets: Death to Twitter Employees Extremists warn of 'lone wolf assassins' By Rob Quinn, Newser Staff Posted Sep 10, 2014 4:46 AM CDT 55 comments Comments ISIS is now threatening Twitter workers in San Francisco. (AP Photo/Militant Website, File) (Newser) – ISIS has got a social media problem and it seems to think it can kill its way out of it. A Twitter account linked to the extremist group has called for the assassination of Twitter employees, apparently in response for the site's attempts to shut down ISIS accounts, reports Vocativ. "The time has arrived to respond to Twitter’s management by directly attacking their employees and physically assassinating them," read one of the threatening tweets from a Jerusalem group that has pledged allegiance to ISIS. "Every Twitter employee in San Francisco in the United States should bear in mind and watch over himself because on his doorstep there might be a lone wolf assassin," read another Arabic-language tweet from the account, which has now been shut down. A spokesperson for Twitter—which shuts down ISIS accounts as soon as they surface—tells Mashable that the company's "security team is investigating the veracity of these threats with relevant law enforcement officials." The company won't say whether it has boosted security at its headquarters in San Francisco, reports the San Francisco Chronicle.