Suspect in Berlin market crash denies involvement - police

German police said it was unclear whether a man they had in custody over the truck used in the terrorist attack on Berlin's Christmas market which killed 12 people was the driver.

President of Berlin police Klaus Kandt told a news conference that the suspect, believed to be an asylum seeker from Pakistan, had denied any involvement in the attack. He was arrested about two miles from the incident.

The truck ploughed into a crowd of people at the popular market, with a further 48 injured, some seriously. Police confirmed that a Polish national was found dead in the truck. He has been identified as Lukasz Urban.

The owner of the trucking company told broadcaster TVN Urban was stabbed and shot to death in the cabin of his truck.

Ariel Zurawski says German authorities asked him to identify him from photos.

"His face was swollen and bloodied. It was really clear that he was fighting for his life," Zurawski said.

Lukasz Wasik, the manager of the trucking company, described 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," Wasik told TVP, Poland's state broadcaster.