The head of MI5 has warned Chinese espionage is on an 'epic scale' in the UK.

Director General Ken McCallum has claimed over 20,000 people have been approached covertly online by Chinese spies.

This warning comes amid a new warning to thousands of British businesses of the risk of having their innovation stolen.

UK correspondent Gavin Grey says more Chinese companies are working to get access to small companies, start-ups and universities, who were largely unaware of security risks.  

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