The state interior minister for Saarland and chairman of Germany's interior ministers' conference, Klaus Bouillon, said it was necessary to hold in-person interviews with Syrian refugees who arrived in Germany last year, as soon as the country's refugee agency (BAMF) had dealt with a backlog of applications.

During the height of last year's refugee influx many Syrians, Iraqis and Eritreans filled out questionnaires instead of being called in for in-person interviews. The measures were intended to lessen the bureaucratic burden. In total, some 890,000 asylum seekers entered Germany in 2015.

"We know, in the meantime, that some people who are dangerous and prepared to use violence have mixed themselves in amongst the refugees," Bouillon said in an interview published in Friday's edition of "Die Welt" newspaper.

While authorities have since resumed carrying out interviews with anyone applying for asylum in Germany, the idea of reinterviewing refugees who filled out the questionnaires was put forward by the Christian Social Union (CSU), the Bavarian sister party to Angela Merkel's Christian Democrats (CDU). Agreeing with its premise, Bouillon said such action had to be taken in light of current threats and that it was also in the interest of those "who had actually fled from the war."

False identities

Of particular concern to Bouillon was the danger that Germany could legalize false identities.

"There are tens of thousands of people who have arrived in Germany whose identities can barely be determined," he said, adding that efforts were underway to clarify refugees' identities using fingerprints and background checks.

There have been several cases this year of Syrians in Germany becoming suspects in terror investigations. In July, a young Syrian blew himself up in Ansbach. In October, Jaber Albakr was found dead in custody after being arrested for allegedly plotting a bomb attack in Berlin.

On Thursday, prosecutors in the German city of Stuttgart said a 20-year-old Syrian refugee who they suspected of plotting to travel to Denmark with explosives had been arrested. There were indications they said that he sympathized with the terrorist organization "Islamic State."

Bouillon's remarks come ahead of next week's conference of German interior ministers, to be held in Saarbrucken.

se/sms (Reuters, AFP, dpa)