German Interior Minister Thomas De Maiziere said on Tuesday that the authorities are still investigating the suspect of the Christmas market attack in Berlin and his background is not yet fully known.
"We are currently interrogating a suspect. We don't know final yet about the background. We will not rest until it has been completely resolved," he said in a video posted on Deutsche Welle (DW) news.
Earlier reports in the German media suggested that a man arrested under suspicion of ploughing a seven-tonne truck through a Christmas market in the heart of Berlin, killing 12, has been named as Naved B, a 23-year-old asylum seeker of Pakistani origin.
Berlin's public radio station RBB-Inforadio reported that the suspect was a Pakistani citizen who entered Germany on December 31, 2015, citing an unnamed security source.
News agency Deutsche Presse-Agentur (DPA), also citing unnamed security sources, reported that he came to Germany as a refugee in February 2016.
Berlin's Tagesspiegel newspaper reported that the man was known to police for minor crimes.
The recent attack was similar to an attack in Nice in July where 86 people were killed by a truck driven by a terrorist inspired by Islamic State of Iraq and the Levant (ISIL).