City in shock: on Tuesday morning, just hours after a truck ploughed into a Christmas market in the heart of the city, candles and roses had been laid near the entrance of a nearby station. Security forces are patrolling trains and train stations, police are on high alert in Berlin as flags fly at half-mast. Streets in the area of the incident remain closed off, and buses have been re-routed
Heightened police presence: Berlin's police office and attorney general have taken over the investigation. The federal prosecutor has also launched preliminary proceedings into the incident. Investigators last night asked the public via social media not to go to the scene of the crime or spread false news
Clean-up efforts: "Our investigators are working on the assumption that the truck was deliberately steered into the crowd at the Christmas market," police said on Twitter. The truck has meanwhile been towed and taken in for a forensic examination. Police are investigating leads that the vehicle may have been stolen from a construction site in Poland
Where it took place: Breitscheidplatz, the square in front of the Kaiser Wilhelm Memorial Church, is a popular tourist destination. To the northeast of Breitscheidplatz is the Berlin Bahnhof Zoo, and to the south is the famous Kurfurstendamm shopping street
What happened: a truck drove straight into a crowded Christmas market in a popular shopping area in Berlin late Monday evening. This image is reminiscent of a similar attack in Nice last July, in which 86 people were killed when a man drove a truck through a crowd. In response to the Berlin tragedy, France has beefed up security at its own Christmas markets
The victims: police have confirmed 12 deaths so far. At least 50 people were injured, some seriously. Rescue workers set up emergency tents on site. The university hospital Charite was ready to accept the injured, according to Berlin Mayor Michael Muller
Searching for suspects: police initially detained a 23-year-old asylum-seeker from Pakistan in connection with the truck attack. Authorities released him on Tuesday, citing a lack of evidence. Berlin police admitted they may have apprehended the wrong suspect. The driver of the truck is believed to be at large. Authorities said one or more fugitives were likely armed and dangerous
'This was a terrorist attack': condolences have been pouring in from all over the world. "A country is united in mourning," Chancellor Angela Merkel told the nation on Tuesday morning. Calling it a terrorist attack for the first time, Merkel described the incident as "cruel and beyond comprehension″
