A truck slammed into a crowded Christmas market in central Berlin on Monday night, killing at least 12 people and wounding 48, in what authorities are investigating as a possible terrorist attack.

The passenger in the truck died in the crash and the suspected driver was arrested near the scene, police said.

Justice Minister Heiko Maas said investigation of the case has been handed over to federal prosecutors, who handle terrorism cases. Interior Minister Thomas de Maiziere told ARD television that authorities were still investigating and did not want to use the word attack, but signs pointed to everyone's worst fears.

"I don't want to use the word 'attack' yet at the moment, although a lot points to it," de Maiziere said. "There is a psychological effect in the whole country of the choice of words here, and we want to be very, very cautious and operate close to the actual investigation results, not with speculation."

The Scania-brand truck plowed up to 80 meters (260 feet) into the Christmas market near the iconic Kaiser Wilhelm Memorial Church, along the Kurfürstendamm shopping mile, at around 8:30 p.m. local time as people were getting off work in the busy shopping district just days before Christmas.

DW correspondent Kyra Levine in Berlin reported that ambulances took the wounded away and streets were closed off, turning a normally bustling area into an eerily calm scene of empty streets as police urged people to stay home.

The truck had Polish license plates and was carrying steel beams. The dead passenger in the truck has been identified as a Polish national, according to police. The Polish owner of the trucking company, Ariel Zurawski, told TVN 24 television that his cousin worked for him and that he couldn't be reached since around 4 p.m. local time.

Zurawski told the broadcaster there was no way his cousin carried out the attack. "Something must have been done to him," he said.

The nationality of the suspected driver in custody is still unknown, but German news agencies "Die Welt" and dpa cited security sources as saying the arrested man was an asylum seeker from Pakistan or Afghanistan. They said he had arrived in Germany in February.

An employee of Zurawski, who spoke to DW on condition of anonymity, said the truck was on its way from Poland to deliver steel to a ThyssenKrupp site in Italy before they lost contact with the assigned driver. According to the shipping company's GPS tracking, from 5 p.m. the truck was at a standstill in the northern Berlin suburb of Wedding for about two hours.

Europe on high alert

The likely attack, one of biggest to hit Germany in more than a decade, comes as Europe is on high alert following a string of terrorist attacks in France and Belgium over the past year. Although no group has claimed responsibility for the incident in Berlin, the so-called "Islamic State" (IS) has previously called on its followers to carry out terror strikes in Europe.

"Even though IS is now greatly weakened as an organization it is still able to inspire terrorists in the West," Max Abrahms, a terrorism theorist at Northeastern University in the United States, told DW. "Everyday items like cars and trucks can be very lethal, making counterterrorism extraordinarily difficult."

The apparent terrorist attack comes after Germany has taken in more than 1 million refugees over the past two years, raising questions over the country's ability to handle such a large number of newcomers. The influx has sparked security concerns and forced the government to heighten security measures ahead of federal elections in 2017, in which Chancellor Angela Merkel's immigration policies are expected to be a central issue.

German authorities have foiled several planned attacks recently, arresting dozens of alleged Islamists. In early October, a Syrian refugee was detained for allegedly planning to bomb a Berlin airport. The suspect, Jaber Albakr, later killed himself while in custody. 

In July, a suspected 17-year-old Afghan refugee wielding an ax and knife wounded five people on a train in Bavaria before being shot dead by police. Days later, a Syrian asylum seeker claiming to act in the name of IS blew himself up at a festival in the southern city of Ansbach, wounding 15 people.

Around the same time, an 18-year-old German-Iranian gunman killed nine people at a shopping mall in Munich before committing suicide. Authorities said the young man, who had planned the attack for a year, was "obsessed" with mass murders and had no links to the IS group.

Earlier this month, a 12-year-old was arrested for allegedly assembling a homemade nail bomb he tried to explode at a Christmas market in the western city of Ludwigshafen.

For a detailed timeline of events, read the archive of DW's live news ticker below.

0056 UTC - The death toll from the truck attack has risen from nine to 12, police said. There are 48 people wounded, some severely.

0025 UTC - German news outlets "Die Welt" and dpa, citing security sources, reported that a man suspected to be the driver who was taken into custody earlier is a registered refugee from Afghanistan or Pakistan. The man reportedly arrived in Germany in February and used several names.

2331 UTC - US President-elect Donald Trump in a statement described a "horrifying terror attack" on innocent civilians celebrating Christmas.  "ISIS ("Islamic State") and other Islamist terrorists continually slaughter Christians in their communities and places of worship as part of their global jihad. These terrorists and their regional and worldwide networks must be eradicated from the face of the Earth, a mission we will carry out with all freedom-loving partners," the statement said. German authorities have so far not described the attack as an act of terrorism, nor has any group claimed responsibility. 

2327 UTC - Interior Minister Thomas de Maiziere told ARD television that much was still unclear about the reason for the truck crash, but hinted that it may have been an attack. "I don't want to use the word 'attack' yet although a lot points to that," de Maiziere said. "There is a psychological effect in the whole country of the choice of words here, and we want to be very, very cautious and operate close to the actual investigation results, not with speculation."

2313 UTC - The White House condemned what it said "appears to have been a terrorist attack." German authorities have so far refrained from stating whether the incident was a terrorist attack. 

2312 UTC - France has increased security at its Christmas markets, the interior ministry said.

2305 UTC - Police said a suspicious item found in the vicinity was only a sleeping bag. 

2303 UTC - Police confirm the truck had a Polish license plate and was carrying steel beams.

2245 UTC - The dead passenger in the truck was Polish, police said. The Polish owner of the truck, Ariel Zurawski, told TVN 24 television that his cousin worked for him and that he couldn't be reached since 4 p.m. local time. He told the broadcaster there was no way his cousin carried out the attack. "Something must have been done to him," Zurawski said. The nationality of the suspected driver in custody is still unknown.

2218 UTC - DW's Brigitta Schülke reporting live from central Berlin speaks to a Syrian refugee: "I escaped war, felt secure. Can't believe that it happened in Berlin."

2214 UTC - Police tell people to avoid nearby Rankestrasse after the discovery of a suspicious item there.

2209 UTC - France announces it will beef up security at Christmas markets after the Berlin truck crash event.

2207 UTC - DW's Kyra Levine has more images from the cordoned-off section of the Christmas market - @KyraGermany:

2204 UTC - Kaiser Wilhelm Memorial Church will hold a memorial service tomorrow at 6pm local time (1700 UTC).

2202 UTC - The Berlin police department will hold a new conference tomorrow at 1pm local time (1200 UTC) with updates on the investigation.

2156 UTC - Berlin's BVG public transport system reports cancelations on several bus lines following the incident.

2150 UTC - DW's Kyra Levine is tweeting live from the scene, where police have cordoned off large sections of the Christmas market - @KyraGermany:

2144 UTC - German daily newspaper "Bild" reports that police are investigating whether the truck might have been stolen.

2138 UTC - Berlin Police tweet phone number to check on missing persons and related questions: 030/54023 111

2133 UTC - Berlin State Interior Minister says the investigation into the truck crash is still unfolding, stressing that it could be an accident.

2129 UTC - Public transport on Berlin subway has reportedly not been affected by the events, despite two underground stations being located nearby.

2118 UTC - French Foreign Minister Jean-Marc Ayrault expresses his "complete solidarity with our German friends."

2117 UTC - Police are asking the public to refrain from sharing videos online from the scene of the attack.

2111 UTC - The investigation has been referred to Germany's Federal Prosecutor General.

2109 UTC - The truck that ploughed into the crowd in Berlin is reported to have a Polish license plate.

2101 UTC - German government spokesman Steffen Seibert tweets: "We mourn the dead and hope that the many wounded can be saved."

2058 UTC - German Interior Minister Thomas de Maiziere has pledged federal police will provide "any necessary assistance."

2054 UTC - Deutsche Welle reporter Kyra Levine is tweeting live from the scene. - @KyraGermany

2052 UTC - German Chancellor Angela Merkel has been briefed on the situation by Interior Ministry officials.

2051 UTC - Berlin Mayor Michael Müller says the situation is under control.

2049 UTC - German news channel N24 says the person in the passenger seat of the attack truck was reportedly killed.

2046 UTC - Suspect under arrest is alleged to be the driver of the truck; however, police have not confirmed this.

2043 UTC - Facebook has activated its safety check feature.

2036 UTC - A suspect has been arrested according to a police source.

2035 UTC - Germany's dpa news agency reports the Scania-brand truck managed to plough up to 80 meters (260 feet) into the crowd at the Christmas market.

2033 UTC - Police have asked for people to stay indoors to assist with unfolding investigation.

2006 UTC - Berlin police have confirmed tally of nine fatalities.

cw, ss/cmk, rc (AFP, AP, dpa, Reuters, epd)