Despite crackdowns by Twitter ( TWTR ), Facebook ( FB ) and Alphabet ( GOOGL )-owned YouTube on Islamic State material on social media sites, ISIS supporters are opening new accounts nearly as quickly as gatekeepers can yank them down, according to a story in the Wall Street Journal on Wednesday. Twitter, which ramped up its anti-terror fight last summer, removed more than 26,000 suspected pro-Islamic State accounts in March, nearly four times the number erased in September, according to an analysis the WSJ said was conducted for the newspaper by Recorded Future, a threat-intelligence firm. ISIS supporters established more than 21,000 Twitter accounts in March, compared with about 7,000 in September, the analysis found. Twitter has 320 million active users worldwide, and new accounts can be created without using a real name. Twitter said in a statement on its website this year that it condemned “the use of Twitter to promote terrorism,” saying it had deleted 125,000 accounts since mid-2015 for threatening or promoting terrorist acts. As a result, the company said, it had seen “this type of activity shifting off Twitter.” The WSJ said that Islamic State operatives mocked the Twitter announcement, sending their own message: A tweet of a bullet-riddled version of the company’s bluebird logo. Companies such CtrlSec are drawing “online hunters around the world to watch for suspected terrorists on social media and other parts of the Web,” said the newspaper’s report. Over the past year, the WSJ said CtrlSec reported identifying about 120,000 Twitter accounts linked to ISIS, including hundreds linked to Islamic State operative Abu al-Walid. At least three of his accounts were reported and deleted on the day of the terror attacks in Brussels, Belgium in March that killed 32 people, the WSJ said. Facebook “Zero Tolerance For Terrorists” President Obama addressed the nation in December after the San Bernardino, Calif., terrorist attack and urged high-tech and law enforcement leaders “to make it harder for terrorists to use technology to escape justice.” After Obama’s speech — which did not name specific companies — Facebook said it “has zero tolerance for terrorists.” The president called the California shooting an act of terrorism that appeared to be inspired, but not directed, by members of the Islamic State in Iraq and Syria, or ISIS. His address came as the killings in Paris in November and in California in December raised concerns that the U.S. and other countries aren’t doing enough to prevent terror attacks. Investigators have said one of the shooters in San Bernardino, Calif., Tashfeen Malik, used a Facebook alias to pledge her allegiance to an Islamic State leader. Facebook said it had removed a profile page linked to one of two people who opened fire in San Bernardino. In a statement to IBD in December, Facebook said, “We share the government’s goal of keeping terrorist content off our site. Facebook has zero tolerance for terrorists, terror propaganda or the praising of terror activity, and we work aggressively to remove it as soon as we become aware of it. If we become aware of a threat of imminent harm or a planned terror attack, our terms permit us to provide that information to law enforcement, and we do.” Twitter stock was up 4% in afternoon trading in the stock market today , while Facebook stock was down 1.5%.