LONDON’S MAYOR BORIS Johnson says that thousands of people in London are being monitored by intelligence agencies in the fight against homegrown jihadists.

Speaking today to the Daily Telegraph, Johnson says that the English capital is “very concerned” about the threat of a terror attack.

“In London we’re very, very vigilant and very, very concerned.

“Every day – as you saw recently, we had to raise the threat level – every day the security services are involved in thousands of operations.

“There are probably in the low thousands of people that we are monitoring in London.”

Britain’s terrorism threat level was raised to “severe” in August, the second-highest, which means that an attack is thought to be “highly likely”.

Intelligence services say the threat comes primarily from the Islamic State (IS) group and al-Qaeda.

The government believes that around 500 people have travelled from Britain and are fighting in Iraq and Syria.

Johnson said that of these, “we think a third, maybe more — maybe half — come from the London area”.

“If and when they come back, we have a real job to deal with them,” he told the Telegraph.

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