- So-called Islamic State (IS) claims responsibility for Monday's truck attack at a Berlin market, which killed 12 people and injured 49
- The registered driver of the Polish lorry is reported to have been found dead with gunshot wounds
- German police have released a Pakistani suspect, saying there is no evidence against him
- German Chancellor Angela Merkel and Berlin Mayor Michael Mueller attend a vigil at the Kaiser Wilhelm Memorial Church
- Mr Mueller says "the entire free world mourns the victims of this cowardly and inhumane attack on our peaceful way of living"
In July, more than 80 people were killed, including children, after a lorry ploughed into a crowd celebrating Bastille Day in the southern French city of Nice.
The attacker was later identified as Tunisian delivery man Mohamed Lahouaiej-Bouhlel.
He was not a known jihadist, but French Interior Minister Bernard Cazeneuve said the killer had apparently been radicalised very quickly.
The co-driver of the lorry died during the incident, a police spokesman tells Germany's N24 TV.
Eyewitness Mike Fox, visiting Berlin from Birmingham, says the large lorry missed him by only about three metres as it drove into the market, tearing through tables and wooden stands.
"It was definitely deliberate," he told Associated Press.
Mr Fox added that he helped people who appeared to have broken limbs, and that others were trapped under Christmas stands.
The suspected lorry driver has been arrested, a police spokesman tells N24 TV.
The police also ask people to stay at home and not spread rumours.
In a tweet (in German), Berlin police confirmed that nine people have been killed and many injured.
The police said many colleagues were at Breitscheidplatz, investigating what happened.
Video footage has emerged of the aftermath of the incident.
The market is at Breitscheidplatz close to the Kurfuerstendamm, the main shopping street in the city's west.
German media are reporting that the driver is on the run.
Welcome to our live coverage as a lorry ploughs into a Christmas market in central Berlin, killing at least nine people and injuring several others.
Police say they believe it was a deliberate attack.