A lorry killed at least 12 people and injured dozens as it ploughed into a busy Christmas market in Berlin on Monday.
Police in Germany said it was a suspected terror attack.
Ambulances and heavily armed police rushed to the area after the vehicle mounted the pavement of the market in a square popular with tourists.
And the horrific scenes are reminiscent of July’s deadly truck attack in the French Riviera city of Nice.
“I don’t want to use the word ‘attack’ yet, although there are many things pointing to one,” Interior Minister Thomas de Maiziere told public television.
As witnesses described scenes of panic and carnage, police said at least 12 people were killed. Police also said 48 others were injured in the incident, which came less than a week before Christmas.
And following the crash, Australian Trisha O’Neill told the Australian Broadcasting Corporation she was only metres from where it happened.
“I just saw this huge black truck speeding through the markets crushing so many people and then 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.”
O’Neill said there was “blood and bodies everywhere”.
A German police spokeswoman told AFP that a man who was apparently driving the truck had been detained while the passenger was dead.
Police later identified the passenger as a Polish national.
Later, security sources cited by DPA news agency said the man behind the wheel was an asylum seeker from Afghanistan or Pakistan. He was said to have arrived in Germany in February.
The daily Tagesspiegel said the man was known to police but for minor crimes, not links to terrorism. The Polish owner of the lorry confirmed his driver was missing.
“We haven’t heard from him since this afternoon. We don’t know what happened to him. He’s my cousin, I’ve known him since I was a kid. I can vouch for him,” transport company owner Ariel Zurawski told AFP.
Lukasz Wasik of the same company said contact was lost with the 37-year old at around 3 pm (1400 GMT). German authorities then said there was no indication of “further dangerous situations in the city near Breitscheidplatz”, where the suspected attack took place.
“We are investigating whether it was a terror attack but do not yet know what was behind it,” a police spokesman said.
German Chancellor reacts
Chancellor Angela Merkel reacted quickly to the incident. Her spokesman Steffen Seibert tweeted: “We mourn the dead and hope that the many people injured can be helped.”
Traditional Christmas markets are popular in cities and towns throughout Germany. The markets have frequently been mentioned by security services as potentially vulnerable to attacks.
“It’s awful. We were in Berlin for Christmas,” said American tourist Kathy Forbes. “We also thought it would be safer than Paris.”