Germany frees suspect in market attack, says perpetrator maybe still at large

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The truck smashed into wooden huts serving mulled wine and sausages on Monday evening at the foot of the Kaiser Wilhelm memorial church, one of west Berlin's most famous landmarks. Forty-five people were injured, 30 severely.

Policemen investigate the scene where a truck plowed into a crowded Christmas market in Berlin. REUTERS/Fabrizio Bensch

Islamic State claimed responsibility the attack, saying the perpetrator was a "soldier" of the militant group.

"He executed the operation in response to calls to target nationals of the coalition countries," its AMAQ news agency said.

But Germany's interior minister said that despite the claim, investigators were following various leads.

"We just heard about the supposed claim of responsibility by this so-called Islamic State that is in fact a gang of terrorists," Minister Thomas de Maiziere told ARD broadcaster. "There are several leads that investigators are following now."

The Chief Federal Prosecutor's Office said in a statement it had been unable to prove that the suspect had been in the cabin of the truck at the time of the attack and said he had denied any involvement.

Earlier, Die Welt newspaper quoted an unnamed police chief as saying: "We have the wrong man. And therefore a new situation. The true perpetrator is still armed, at large and can cause fresh damage."

Commenting on the suspect's release, de Maiziere told ZDF television: "That's why it is true that one cannot rule out that the perpetrator is still at large."

He said there was no doubt the Berlin incident had been an attack but the motive remained unclear. He also said it was not yet known how many foreigners were among the victims of the attack but no children had been among the dead.

News of the arrest of the 23-year-old Pakistani had led politicians in Germany and beyond to demand a crackdown on immigration, but Chancellor Angela Merkel urged caution.

"There is much we still do not know with sufficient certainty but we must, as things stand now, assume it was a terrorist attack," she told reporters earlier on Tuesday.

"I know it would be especially hard for us all to bear if it were confirmed that the person who committed this act was someone who sought protection and asylum," she said.