An undercover report has revealed some of the tactics migrants use to game Germany’s immigration system, and that 80 per cent of those seeking asylum in the country have no papers.

Abdullah Khan, who worked four months undercover at a reception centre, reported how large numbers of migrants use fake documents and lie so as to qualify for as many taxpayer-funded benefits as possible.

The journalist, who after his time working at the reception centre believes there are “far too many people living in Germany”, regularly found himself suspecting people claiming to have fled fighting in Syria were actually economic migrants.

Mr. Khan noted some of the most common tricks migrants use. He recounted: “Many pose as minors travelling alone, because word has spread that they will qualify for more benefits. … To lie about their age, many people use false passports and other identity documents.”

The federal police found that eight out of ten migrants seeking asylum in Germany come without any identification papers. Mr. Khan reported that the majority claim to have lost their documents “while fleeing”, and claim to be Syrian as this gives them the best chance of being granted “refugee” status.

Ninety-six per cent of migrants claiming to be from Syria were awarded refugee status by the government in 2015. In his four months working undercover Mr. Khan was outraged to discover many asylum applications from people claiming to be Syrian were accepted without even an interview.

The Bild journalist noted that under this “accelerated procedure” for Syrians, abolished at the beginning of this year, applicants just had to say they were from Syria and sign their name on a form — translators did the rest.

One example Mr. Khan detailed was that of a migrant who claimed to be Afghan. Wearing expensive designer sportswear, which he claimed was given to him at another asylum centre, the man spoke in Urdu.

Son of Pakistani immigrants, the journalist immediately grew suspicious given that Urdu is a Pakistani language, not Afghan. Asked for his passport, the migrant swore he’d lost it on the trip to Germany. When he finally produced an Afghan one, Mr. Khan immediately recognised it as a fake.

Many migrants employed a variety of tricks to avoid their fingerprints being taken, Mr. Khan stated.

“Again and again it happens that applicants manipulate their fingerprints. Grease, acid or superglue on their fingers. Others grind their fingertips,” he revealed.

The journalist explained: “Some want to avoid the fact that [their data] is recognised on the crime register. Or that it is noted that they have already been registered in another country.”

The journalist detailed a typical day’s work where he was overseeing five cases, and wrote: “I know that two applicants [on this day] have made false declarations.

“A particularly brazen one was an applicant who allegedly came from Morocco. He looked like he was 65 years old, but stated that he was 30. Even my colleagues laughed.”

Mr. Khan said hearing case after case where migrants claimed to have fled from Islamic State and barrel bombs presented him with the same dilemmas each day.

“Am I being lied to by economic migrants, who do not qualify for asylum, but just hope for a better life in Germany? Or is an ISIS sympathiser sitting in front of me?” the journalist recalled thinking.

Mr. Khan concluded: “On all these issues I have no answers. All I know is that currently there are far too many people living in Germany, and we do not know where they really come from, what they really intend and why they are really here.”

The migrant who pledged allegiance to Islamic State before launching into a terror rampage on a train in Bavaria was thought to have been a Pakistani who lied about being Afghan in order to have a better chance of securing asylum in Germany.