Twitter has suspended more than 125,000 accounts since mid-2015 “for threatening or promoting terrorist acts.”
In a blog post, Twitter said the accounts were “mostly linked to ISIS.”
“We condemn the use of Twitter to promote terrorism,” the statement said, adding that it had increased its review teams to respond more quickly.
Twitter has more than 500 million users worldwide.
“We’ve already seen results, including an increase in account suspensions and the transfer of this type of activity from Twitter,” said the company.
Twitter added that it cooperates with law enforcement “when appropriate” as well as other organizations.
Governments around the world are urging social media companies to take stronger action to tackle online violence.
In December 2015, US politicians introduced a bill that would force such companies – including Twitter and Facebook – to report any apparent terrorist activity they discovered.
EU officials are also calling for talks with major companies on social media to discuss the issue.
In March, Facebook revised its “community standards” to include a separate section on “dangerous organizations.”
Facebook has said it will ban groups promoting “terrorist activity, organized crime or incitement to hatred.”