Updated

A large trove of documents seized in Syria from the Islamic State (ISIS) reveals thousands of plots to attack Europe and other parts of the world, Britain's top commander in the region has said.

More than 10,000 documents and a huge amount of digital data were seized after the group was driven out of Manbij in northern Syria in August, according to Maj. Gen. Rupert Jones.

"If we want to keep Britain safe, we need to deal with Daesh," he said, using another name for the extremist group.

The news comes as anti-terror police have started deploying on London's streets.

General Jones said: "External operations have been getting orchestrated to a very significant degree from within the caliphate, critically from within Raqqa and from within Manbij.

"They were key external operations hubs. There is a huge amount of intelligence, documentation, electronic material that has been exploited there that points very directly against all sorts of nations around the world."

He declined to discuss details of the suspected plots as he spoke to reporters at the Al-Assad air base in Iraq. British security services are analyzing the material.

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