Ambulances and police rushed to the area after the driver drove up the pavement of the market in a central square popular with tourists, in scenes reminiscent of the deadly truck attack in the French city of Nice in July.
"There are at least 50 injured... some seriously. Some are dead," a police spokeswoman told AFP.
Police subsequently said nine had been killed and that one person has been detained over the incident -- which comes less than a week before Christmas.
Audio in Punjabi: Australia advised caution while visiting Christmas markets
Local police say one person has been detained over the suspected attack.
"We are investigating whether it was a terror attack but do not yet know what was behind it," a police spokesman said.
"I heard a big noise and then I moved on the Christmas market and saw much chaos...many injured people," Jan Hollitzer, deputy editor in chief of Berliner Morgenpost, told CNN.
"It was really traumatic."
Witness video from #Berlin #Breitscheidplatz #truck pic.twitter.com/24tyJn3K3W — Chris Koseloglou (@chriskose) December 19, 2016
Washington Post is reporting that the so called Islamic State has claimed responsibility for the attack.
