BERLIN (Reuters) - Germany should be able to deport unaccompanied minor refugees who commit crimes if their families can be identified, the head of the pro-business Free Democrats (FDP) said in remarks released ahead of publication on Sunday.

FILE PHOTO: Free Democratic Party (FDP) leader Christian Lindner arrives for the board meeting at the party headquarters in Berlin, Germany, November 20, 2017. REUTERS/Hannibal Hanschke

FDP leader Christian Lindner spoke amid growing debate about unaccompanied refugees after the fatal stabbing of a 15-year-old German girl on Wednesday by a suspect later identified by police as her former boyfriend, a 15-year-old Afghan refugee who had entered Germany in early 2016.

Lindner told the Bild am Sonntag newspaper that authorities should be able to deport unaccompanied minors who resisted “educational measures” and caused problems, if their families could be identified in their home countries.

The girl who was killed had filed charges days earlier accusing the Afghan teenager of harassing and threatening her after she broke up with him, police officials said.

The number of unaccompanied minors among migrants entering Germany fell sharply in the first 10 months of 2017 to 8,107 from nearly 35,939 in 2016 and 22,255 a year earlier, according to the German Federal Office of Migrant and Refugees (BAMF).

Although seen as a domestic dispute, the stabbing case has touched a nerve as German cities tighten security for New Year’s Eve celebrations amid continued concern about possible Islamist attacks and after the mass groping of women in Cologne on New Year’s Eve 2015.

Many far-right commentators have seized on the stabbing and the 2015 Cologne incident to justify their anti-migrant and anti-Muslim rhetoric.

In Berlin, police are erecting a special safety zone for women at the mile-long street that runs from the Brandenburg Gate to the Victory Column in the capital’s Tiergarten park.

In the interview, Lindner also renewed his criticism of Chancellor Angela Merkel’s decision in 2015 to open the doors to over a million migrants, mostly from the Middle East and Afghanistan, without adequate controls.

“We need a new immigrant policy in Europe that ensures that the problems are addressed,” Lindner said, noting that securing borders could help prevent right-wing populists from spreading xenophobic sentiment.

“Our country will only stay tolerant and open to the world if people can rely on our legal system at any time and any place,” he said.

The FDP last month withdrew from talks with Merkel’s conservatives and the environmental Greens on forming a new government after the September election. But migration will also be a key topic in upcoming coalition talks between Merkel’s conservatives and the center-left Social Democrats (SPD).

Conservatives want to limit the number of refugees admitted each year to 200,000 or less; the SPD rejects any such cap.