LONDON -- Britain's interior minister has proposed new powers to bar people with extremist views from appearing on television or publishing on social media even if they are not breaking any laws.

Home Secretary Theresa May told a conference of the governing Conservatives that if re-elected next year the party will introduce powers to disrupt people who "spread poisonous hatred" even within the law.

May said Tuesday that only a minority of extremists are violent, but there is "a thread that binds" nonviolent extremism to terrorism.

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May says tougher powers are needed to stop young people becoming radicalized. She says at least 500 Britons have travelled to Syria and Iraq, mainly to fight with militant groups.

Tuesday morning, speaking to the BBC, David Cameron said, "the problem that we have had is this distinction of saying 'we will only go after you if you are an extremist that directly supports violence' it has left the field open for extremists who know how not to step over the line."

Cameron spoke on the heels of the release of radical Islamic preacher Anjem Choudary, who was picked up along with eight other men on Sept. 25 and held for just one day.

Choudary, who had faced similar detentions in the past, and the other suspects were arrested on suspicion of encouraging terrorism.

Civil libertarians, and some Conservatives, call the proposed measures an unacceptable restriction on freedom of speech.

Conservative lawmaker David Davis told the BBC that "we have to be careful we don't end up like the people we are trying to defeat."