The driver of a lorry which ploughed into the crowd at a Berlin Christmas market was stabbed and shot to death in its cabin becoming the first victim of the attack, the owner of his Polish trucking company has claimed.

Ariel Zurawski said German authorities asked him to identify the victim, Lukasz Urban, 37, from photos.

"His face was swollen and bloodied. It was really clear that he was fighting for his life," Mr Zurawski told the broadcaster TVN.

Lukasz Wasik, the company's manager described Mr Urban as a "good, quiet and honest person" devoted to his work.

I believe he would not give up the vehicle and would defend it to the end if were attacked," Mr Wasik said in comments carried by Poland's state broadcaster. TVP.

The truck crashed into people gathered around wooden huts serving mulled wine and sausages outside the ruins of the Kaiser Wilhelm memorial church in West Berlin, killing at least 12 people and injuring 48 others.

Mr Zurawski said his wife had been trying to contact him hours before the attack took place on Monday evening but no one had been able to reach him since midday.

He added there was no way his cousin would have been a willing participant in the attack.

“This is my cousin. I've known him since I was born," He told Polish TV channel TVN24. "My scenario is that they did something to the driver – they hijacked this vehicle because it was practically in the centre of Berlin and they had a good vehicle with which they could do what they did.”

He said the lorry had been travelling from Italy to Berlin laden with heavy steel.

German police said they are treating the act as a deliberate terror attack and have arrested a 23-year-old Pakistani asylum seeker called Naved B. However, police sources told local media that they were uncertain if he was linked to the atrocity.

The attack has been likened to a similar lorry attack on a Bastille Day crowd in Nice in July.

The suspect reportedly ripped off his mask after he was arrested by German police and is now in police custody under armed guard.

Berlin Christmas market lorry attack Show all 18 1 /18 Berlin Christmas market lorry attack Berlin Christmas market lorry attack Several people have been killed after a lorry drove into crowds at a Christmas market in Berlin REUTERS/Fabrizio Bensch Berlin Christmas market lorry attack 'At least nine' people have been killed and more than 50 injured. AP Berlin Christmas market lorry attack Emergency Services rush a Berlin market victim to an ambulance Associated Press Berlin Christmas market lorry attack Police cordoned off the square at Kaiser Wilhelm Memorial Church following the incident REUTERS Berlin Christmas market lorry attack Rescue workers inspect the lorry that crashed into a Christmas market close to the Kaiser Wilhelm memorial church in Berlin EPA Berlin Christmas market lorry attack Emergency crews inspect the lorry that ploughed into a Berlin Christmas market, killing at least nine people AFP Berlin Christmas market lorry attack Fire crews attend the scene of the attack AFP/Getty Berlin Christmas market lorry attack Armed police secure the site of a lorry attack at a Christmas market in Berlin REUTERS Berlin Christmas market lorry attack Crushed debris is visible beneath the wheels of the vehicle REUTERS Berlin Christmas market lorry attack An injured man is pushed to an ambulance REUTERS Berlin Christmas market lorry attack Medics attend an injured person after the lorry attack which killed at least nine and injured more than 50 people AFP/Getty Berlin Christmas market lorry attack Firefighters examine the lorry which was rammed into a Berlin Christmas market REUTERS Berlin Christmas market lorry attack A person is carried into an ambulance REUTERS Berlin Christmas market lorry attack View of the lorry that crashed into a Christmas market in Berlin, killing at least nine and injuring at least 50 people AFP/Getty Berlin Christmas market lorry attack Rescue workers push a person on a stretcher to an ambulance Getty Berlin Christmas market lorry attack Firefighters assess the damage after the lorry rammed the Christmas market, killing 'at least nine', and injuring more than 50 people AP Berlin Christmas market lorry attack Firefighters stand beside a toppled Christmas tree at the site of the suspected terrorist attack in a Berlin Christmas market AP Berlin Christmas market lorry attack Damaged stalls at the scene of the incident at a Berlin Christmas market where at least nine people have been killed EPA

Berlin's public radio station RBB-Inforadio cited security sources saying the man entered Germany on 31 December 2015.

News agency dpa, also citing unnamed security sources, said 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.

Police urged people to stay in their homes on Twitter and encouraged them to use the Facebook safety check feature to tell loved ones they are safe.

One eyewitness described “blood and bodies everywhere” after the truck ripped through the crowd.

Australian student Trisha O’Neil said “All of a sudden there was a big boom and the people in front me jumped on top of me.

“All the lights went out and everything was destroyed.

“I could hear screaming and then we all froze. Then suddenly people started to move and lift all the wreckage off people, trying to help whoever was there.”