The UK home secretary has called on the international community to "destroy ISIL (The Islamic State)" as she proposed a raft of powers to access private communications data and curb extremists' freedom of movement and expression.
Banning orders and "extreme disruption" orders, which will give the UK government powers to restrict the movement, activities and social media use of extremists, will be included in the Conservatives' manifesto for the 2015 election, Theresa May told the party's autumn conference.
A new counter-terrorism bill, which would allow for the confiscation of passports of Britons who travelled to fight in Iraq and Syria, will also be introduced in November, May confirmed.
She announced plans to resurrect the Communications Data bill — or so-called "snoopers' charter" — which would give police and security services wide-ranging internet surveillance powers.
New "banning orders" will be unveiled in the next Conservative manifesto, aimed at allowing the authorities to outlaw any extremist group, even if they do not pose a terrorism threat.
The practical implications of such orders could be the curtailment of public or online comment and campaigning, including social media use.
In addition, the establishment of "extremist disruption orders" would be used to target individual radical preachers, restricting their movement and activities.
May also said it would become a criminal offence to prepare and train for terrorism overseas, admitting that most British fighters fighting for the Islamic State "are likely to return".
Emphasising the threat posed by ISIL, she said: "With the capability of a state behind them, the terrorists could acquire chemical, biological or even nuclear weapons to attack us."
She added: "While we still have the chance we must act to destroy ISIL."
In a speech that received a standing ovation from the audience in Birmingham, the home secretary said she planned to resurrect the Communications Data bill blocked by the "outrageously irresponsible" Liberal Democrats two years ago.
The new powers would allow police and security services to compel any communications provider to hand over user data.
May said that the NCA had estimated it had to drop "at least 20 cases" and the Metropolitan Police had to drop 12 cases in three months as a result of missing communications data.
Arguing that a diminished capability for police to access such data was allowing organised crime to continue undisturbed, crimes to go unpunished and children to be abused, May said: "if we do not act we risk sleepwalking into a society in which crime cannot be investigated."
May also renewed her commitment to reform stop and search, stating that "more than a quarter of a million stops carried out last year were probably illegal."
Describing it as "hugely damaging" to public confidence in the police, she said: "Nobody should ever be stopped and searched because of the colour of their skin."
Responding to the home secretary's speech, Shami Chakrabarti, director of Liberty, told VICE News:
"There were startling contradictions in the home secretary's speech, seeking civil liberties sainthood by tightening stop and search whilst granting police powers to seize passports at the borders and blanket internet surveillance on the whole population.
"She gave a good sermon about human rights and the rule of law in the Middle East whilst mocking the Court of Human Rights and proposing to ban non-violent speech and organisations. How do you promote liberal democratic values by promising state powers worthy of a caliphate?"
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