Twelve people died when a lorry drove through the crowded Breitscheidplatz market.
At least another 48 were injured.
So far five of the dead have been officially identified: the Polish lorry driver who is said to have tried to stop the attacker, a 60-year-old Israeli woman who was visiting Berlin with her husband, an Italian expatriate woman and two Germans from the federal state of Brandenburg who have not yet been named by the authorities.
A German woman from Neuss, near the west German city of Duesseldorf, is believed to be among the dead. Her son, aged 40, is among the injured.
In total, it is believed six Germans died in the attack, although five people remain unidentified, according to German website RP Online.
The 37-year-old Polish lorry driver was found dead in the passenger seat, with both gun and knife wounds.
Investigators quoted by German media say there is evidence that, despite being stabbed, Mr Urban wrestled the driver for the steering wheel.
One official quoted by Bild newspaper said it appeared from the post-mortem examination that the driver had survived up to the attack and was shot dead when the truck came to a halt. No gun has been recovered.
Ariel Zurawski, the owner of the Polish transport company, said he had been asked to identify Mr Urban from photographs.
"His face was swollen and bloodied," he told broadcaster TVN. "It was really clear that he was fighting for his life."
Company manager Lukasz Wasik described Mr Urban as a "good, quiet and honest person" and said he believed he would have defended the lorry "to the end".
Israeli tourist Dalia Elyakim, 60, was confirmed to have been among the dead after her body was identified on Wednesday evening. Her husband Rami was seriously injured.
Israeli President Reuven Rivlin said he had received the news of Mrs Elyakim's death "with great sadness", the Jerusalem Post newspaper reported.
Mr and Mrs Elyakim, from Herzliya just north of Tel Aviv, were both at the Christmas market when the lorry drove through the crowd.
Mr Elyakim remains in hospital after undergoing surgery.
The Italian expatriate was confirmed by the Italian foreign ministry on Thursday to have been among those killed in the attack.
Ms di Lorenzo's family grew concerned after they lost contact with her on Monday. Her phone and metro pass were later found at the scene in Breitscheidplatz market.
Ms di Lorenzo, 31, from Sulmona near L'Aquila, worked for a transport company in Germany and lived in Berlin.
Her father, Gaetano, earlier  told La Repubblica that the family were "waiting for confirmation" and had "no illusions" on her safety.
Ms di Lorenzo's mother and brother have travelled to Germany to try to identify her.
Two Germans from the federal state of Brandenburg - a 32-year-old man from Brandenburg an der Havel and a 53-year-old woman from Dahme-Spreewald - were also among the dead, the state's interior ministry said.
As police continue to hunt for the person behind Monday's attack on a Berlin Christmas market, the names of the first victims have started to emerge.