Twelve people were killed and scores injured when a lorry ploughed into Christmas market shoppers in the centre of the German capital, Berlin.
The authorities are not yet sure if the incident was a deliberate attack or an accident but one man was arrested nearby.
The German President Joachim Gauck said it was “an awful evening for Berlin and for our country”.
The Christmas market was taking place just off one of the city’s most famous shopping streets, the Kurfurstendamm, in Breidscheidplatz.
A Polish company is said to own the lorry which crashed into shoppers and stalls.
The Mayor of Nice in France where 86 people were killed in July when a lorry was deliberately driven into crowds of people tweeted: “Support for the mayor of Berlin and the German people”.