Computer firm Microsoft is hurrying to fix a bug with the Internet Explorer browser after it emerged that hackers have already exploited the glitch with attacks on US companies.
Microsoft said the bug could allow hackers to take over a computer, install malicious programmes and create user accounts.
Cybersecurity firm FireEye said so far there had been "targeted attacks seemingly against U.S.-based firms, currently tied to defence and financial sectors".
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The Labour leader did not say whether he would maintain Britain's nuclear deterrent programme.
Ukip leader Paul Nuttall also said he would want to get rid of Sharia courts.
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