Home Secretary Theresa May has said the government is doing everything possible to counter extremist groups operating in Britain.
Speaking at the Community Security Trust annual dinner in central London on Wednesday evening, Mrs May said more would be done to stop extremists "masquerading as charities" in order to raise funds.
Mrs May praised the Charity Commission's efforts to take a "more effective and aggressive line in seeking out and ejecting" such organisations.
"Too often organisations whose purposes have been the opposite of charitable - and which have even been involved in sending money to straightforwardly terrorist organisations - have been allowed to flourish as charities," said the Home Secretary.
But she warned that the "battle against intolerance and extremism, and the murderous violence it spawns, is not going to end soon".