GERMAN spies have rumbled at least 20 Muslim extremists with their nation's army - weeks after finding 60 within the ranks.

A major top level probe is underway to carry out security checks on every would-be Bundeswehr recruit after ISIS sympathisers were rooted out by the military counterespionage service.

4 Intruders ...Jihadis loyal to the ISIS flag are joining the German army Credit: Alamy

4 Well trained ....German troops are among the world's most skilled Credit: Reuters

4 Gamble ...Chancellor Angela Merkel is relaxed about mass migration from ISIS war-zones Credit: Reuters

Military spooks fear a web of “sleepers” could be threading itself within Germany's armed forces and one day they will turn their guns on their own comrades.

Worse still it is feared ISIS cells could be joining up to become army pros, gaining detailed knowledge of guns, ammunition and explosives - before turning renegade and inflicting atrocities.

Germany is on high alert following a spate of deadly attacks last July, two of which were claimed by the Islamic State in Iraq and the Levant (ISIS).

Numerous terror plots have been foiled in the past few months.

On Thursday German cops swooped on a Syrian man suspected of plotting a terror attack on a city airport in Berlin.

Just less than two weeks ago 13 properties in Germany were searched and at least one arrest made.

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A number of computers, notebooks and other material relating to Jihadism were seized.

In early October in the eastern city of Chemnitz, when a 22-year-old Syrian national was captured after a two-day manhunt.

He later killed himself in jail.

German spy chief Christof Gramm said: “We’re seeing the risk that the Bundeswehr can be misused as a training camp for violence-ready Islamist.

“We would like to see if there are future doubts about the loyalty of future soldiers.

“What if a Bundeswehr-trained Islamist did something and we hadn’t noticed?”

4 Ticking time bomb ..German squaddies could be attacked by one of their own Credit: Reuters

The fresh discoveries of jihadi sympathisers comes after 60 were found in August.

At least 20 ex-Bundeswehr soldiers are feared to have left Germany to use their highly regarded military skills fighting for ISIS in the Middle East.

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