We are pausing our live coverage of the investigations over Monday's lorry attack in Berlin. Here's a round-up of the latest:

• So-called Islamic State has said one of its "soldiers" carried out Monday's attack; the identity of the attacker has not been established
• German Interior Minister Thomas De Maiziere reacted cautiously to the claim, saying "several lines of investigation" were being pursued.  
• Prosecutors have freed the only suspect, citing insufficient evidence. He was identified by media only as Pakistani national Naved B.
• You can find all the latest developments here
• Here's what we know so far about the attack
• Read more about previous attacks in Germany

Image source, AFP

The claim of the lorry attack in Berlin by so-called Islamic State (IS) does not prove much in terms of the attack. The group often refers to individuals who carry out attacks as its "soldiers" but the crucial question is firstly whether the individual had any form of direct contact with IS.

Face-to-face or online communication are possible but far from certain. If there was no direct contact, it could still be the case that an individual was inspired rather than directed by the group.

In this case, an individual may leave his or her own pledge of allegiance in written form or online or in a video.

But until such evidence emerges, it remains hard to know if this is just an opportunistic claim by the group rather than one based on real substance.

The truck which was used to carry out the attack was probably equipped with all the latest technology to prevent an accident, including an emergency braking system, Die Welt (in German), external says. 

But it points out that such technical aids can be over-ruled or disabled by the driver, backing up the "man before technology" motto which insists a human rather than a machine should ultimately be in control. 

However this internationally accepted regulation is increasingly colliding with new developments in automated or autonomous driving, the paper says, even though experts at present say the technology is not available for a bystander to stop an out-of-control truck.

Image source, AFP

German Interior Minister Thomas de Maiziere told ZDF television that it was beyond doubt that the truck incident was an attack, but that the motives remained unclear.

He added that it was still unclear if there were any foreigners among the victims, but said that there were no children among the dead, Reuters news agency reports.

Germany's Interior Minister Thomas De Maiziere has reacted cautiously to the claim by the group known as Islamic State that it carried out the attack.

"This alleged claim of responsibility of the so-called Islamic State, which in reality is nothing but a gang of terrorists, only just came in. Until then there wasn't any claim," he said.

"Sometimes they [the claims] are issued somewhat later... There are several lines of investigation we are pursuing. We should let the security services do their job. They are working hard and no one will stop until the perpetrator or the perpetrators have been arrested."  

"After Berlin, Angela Merkel’s open door to migrants might be about to slam shut," writes Josef Joffe in The Guardian, external.

"Recall last year when she flung the country's doors wide open. Proclaiming "wir schaffen das" - we can do it - she essentially relinquished control over Germany's borders. 

"Some 800,000 people from the Middle East as well as North Africa arrived. 

"Merkel now says that if the perpetrator is indeed a refugee, 'this would be extremely hard for us to bear', and it 'would be particularly repugnant for all those Germans, who toil daily to help refugees'. 

 "Thus do good intentions come to a nasty end," Josef Joffe comments. 

Read the BBC's comprehensive profile of the group known as Islamic State.

The group known as Islamic State claims responsibility for the truck attack - its self-styled Amaq news agency says.

The Polish owner of the truck used in the attack has said the dead man on the passenger seat was his employee and cousin.

Ariel Zurawski said that Lukasz Urban, 37, was a "good guy", AFP reports. 

Police said he appeared to have been stabbed and shot. 

"One person would not have been able to overpower him," Mr Zurawski said, describing his cousin as a heavyset man who weighed 120kg (265lb) and stood 183 cms (6ft) tall. 

"We could see injuries. His face was bloodied and swollen," Zurawski told private news channel TVN 24, referring to a photo of the body he received from Polish police. 

"There was a stab wound. Police also told me there was a gunshot wound," he said, adding that the dead man's family - including his widow and 17-year-old son - were in shock.

Image source, Getty

As investigators try to work out the motive of a driver who drove the killer lorry on Monday in Berlin, new data shows that European authorities are not just guarding against terror plots using weapons like trucks or bombs, The Washington Post says., external

"They are also concerned about a more conventional threat: illegal firearms that may be increasingly easy for suspected terror networks to obtain".

Citing figures released by the International Center for the Study of Radicalization and Political Violence at King's College London, the paper says that "criminals-turned-terrorist suspects" are increasingly becoming a problem. 

"The research center collected extensive data on 79 recent European militants with criminal pasts. About 80% of those involved in recent terrorism plots had criminal convictions," the paper says.

Damian Grammaticas
Europe correspondent

Image source, AFP

For Angela Merkel the legacy of the Berlin attack will be political. It’s not clear who the perpetrator was. But if it proves to be someone who came as a refugee, the German chancellor will face more pressure.

She has stuck to her welcoming policy towards refugees fleeing war and persecution, and a majority of Germans have continued to back her. But Mrs Merkel’s political opponents, notably the far right Alternative fur Deutschland, have attacked her again following the Berlin attack, saying she has compromised Germany’s security by letting in people without knowing who they are.

It’s a charge they will seek to press as Germany gears up for federal elections next year. The AfD had surged in regional elections this year. But Germany’s main parties have all said they will shun any question of sharing power with the AfD next year. And Angela Merkel has seen her support rise in recent polls.

It’s why the issue of who carried out the Berlin attack is vital for Mrs Merkel and her vision of a free, open Germany.

Cologne's main train station was briefly evacuated after a telephone bomb threat, but it turned out to be a false alarm, a German police spokesman was quoted by Reuters news agency as saying.

This user posted on Twitter a picture that, he said, showed the station being evacuated.

German prosecutors say the Pakistani man who was arrested after Monday's truck attack in Berlin has been released because of "insufficient evidence".

The man detained, who had denied involvement, arrived in Germany at the end of last year. He was captured in a park after reportedly fleeing the scene. 

"The accused, detained over the attack on the Berlin Christmas market on December 19, 2016, was let go on this evening on the orders of the federal prosecutor," his office said in a statement.

"The forensic tests carried out so far did not provide evidence of the accused's presence during the crimes in the cab of the lorry."

Image source, Reuters

The Pakistani suspect arrested after Monday's attack has been released, media reports say.

Berlin Mayor Michael Mueller and German Chancellor Angela Merkel are among hundreds of people taking part in a vigil at the Kaiser Wilhelm Memorial Church - next to the scene of the attack. 

Addressing the gathering, Mr Mueller said: "Together we remember the victims of this horrific attack and we stand with the relatives and friends in this difficult hour and say: you are not alone.

"We share your pain; the whole of Berlin, the entire free world mourns the victims of this cowardly and inhumane attack on our peaceful way of living." 

"If the attack in Berlin marks the start of a French-style jihadist campaign in Germany, it could herald a turning point in the country’s politics," the Economist says.

"Conscious of its historical burden and bound by its political system to put moderate, consensus-oriented coalitions into power, Germany is unusually immune to populist sensationalism compared with many of its neighbours. 

"But that may not last if the killing goes on."

Hundreds of people have gathered around a church at the square near the scene of Monday's attack to commemorate the victims.

Deutsche Welle reporter Birgitta Schulke tweeted that church bells were ringing as the ceremony was about to start.