German Chancellor Angela Merkel’s policies on immigration have been “fatal” to Germany, the countries former top domestic intelligence chief has said.

Hans-Georg Maassen, the former head of the Office for the Protection of the Constitution (BfV), roughly the equivalent to Britain’s MI5 or the FBI in the United States, ran the German intelligence for six years, including during the height of the European migrant crisis in 2015.

Maassen, is currently running as a candidate for the German parliament, the Bundestag, under Angela Merkel’s supposedly centre-right Christian Democrat Union (CDU).

In an interview with The Times of London, the former spy chief said that the German people could not understand the “fatal migration policies” taken by Merkel, which allowed some 1.2 million migrants into the country.

“[Germans] simply cannot understand why ever more people are coming into this country even though they obviously have no right to asylum; why we aren’t deporting them and why politicians just put up with the fact that the people here are falling victim to these migrants,” Maassen said.

He said that under Merkel’s leadership, the CDU as a party has “clearly taken a lot of damage,” explaining: “It’s become a club for electing the Chancellor under the slogan ‘We want Merkel re-elected’, but the actual political and programmatic substance is gone.”

While he described Merkel, 66, as a “strong-willed woman and a top political performer” and praised her role in the eurozone financial crisis, he said the country had taken several painfully wrong turns.

“I just think it’s a shame that we are falling far below our potential in Germany,” he said. “I have the impression that many people have made their peace with the fact that we are declining ever further politically and economically.”

Last August, Chancellor Merkel said that she would “make essentially the same decisions” when questioned if she regretted the decision to open Europe’s doors to mass migration.

The result of her open borders policies has been a massive demographic shift in Germany, with some 26 per cent of the population, or 21.2 million people, now classified as being of a “migrant background”, meaning that they are either migrants themselves or had at least one parent who was born in another country.

It is expected that at least one-third of the population of Germany will have foreign backgrounds by 2040, with major cities likely to see as much as 70 per cent of their population having migrant backgrounds.

With Angela Merkel stepping down from her reign as Chancellor later this year, the future of her party remains in question, with more right-leaning candidates such as Hans-Georg Maassen gaining ground within the CDU.

Maassen was forced out of his role as the leader of the Office for the Protection of the Constitution after it was alleged that he had “far-right” sympathies following his questioning the veracity of videos posted online that allegedly showed migrants being chased through the city of Chemnitz by right-wing extremists, despite evidence to the contrary.

Mr Maassen has denied that he has far-right beliefs, saying that he sees himself as a “fighter for the liberal democratic basic order itself, for a liberal constitutional state.”

“What is happening in this country worries me—that we are slipping into an authoritarian state, into a state-sponsored cowardice, he told the left-wing Telos magazine last week.

“I want people to notice where we are going and to become citizens, not subjects who are wards of the state that provides them with everything they need to live. Many people have lost the ability to lead a self-determined life, to take risks,” Maasen said.

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