Kim Hjelmgaard

USA TODAY

BERLIN — German authorities scoured the nation and other European countries Wednesday for a Tunisian asylum seeker sought in connection with the truck rampage at a Christmas market that killed 12 people.

Investigators don't know whether there is more than one perpetrator at large. In the truck, documents were found belonging to a Tunisian national identified by police as Anis Amri, who turns 24 on Thursday.

He was described as average height and weight, with black hair and brown eyes. German authorities offered a reward of up to 100,000 euros for his arrest. “Caution: He could be violent and armed,” a notice warned. Police released a picture of him.

Amri was under covert surveillance for several months after a tip from Germany's federal security agencies, according to the Associated Press. His birthdate is listed in the warrant as Dec. 22, 1992, according to the AP.

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Authorities suspected he might try to buy a weapon to use in an attack. The surveillance was called off in September.

Interior Minister Thomas de Maizière said the search for the suspect extended to other countries in Europe's border-free zone.

German lawmaker Stephan Mayer said after being briefed by security officials Wednesday that Amri, whose wallet was found in the truck, is thought to have links to Islamic extremists. He said Amri was supposed to be deported from Germany this year.

Ralf Jaeger, the interior minister of the state of North Rhine-Westphalia, where Amri registered for asylum, said authorities rejected his asylum application in July.

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German weekly magazine Spiegel reported that Amri is known by several aliases and has three nationalities.

A previous suspect, a 23-year-old Pakistani asylum seeker, was released Tuesday evening because prosecutors did not find enough evidence linking him to the incident. He denied any involvement in the assault.

Another suspect was held overnight and released Wednesday because of insufficient evidence, the RBB broadcaster reported.

Germany is treating the attack as terrorism, which the Islamic State said was carried out by a "soldier."

No evidence has established a connection to the militant group, which has staged and inspired assaults across Europe and the USA.

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German President Joachim Gauck met injured victims of the attack at the Charite hospital in Berlin on Wednesday.

He said his meeting with a man who was hit by a beam while helping an injured person "reminded (the victims) of their innate strength."

Locals and refugees sang together in memory of the victims Wednesday near the Kaiser Wilhelm Memorial Church, close to the scene of the attack.

Berlin police urged people to be especially alert and warned that the person or people responsible were probably armed and dangerous. As of Tuesday night, police had received more than 500 tips about the attack. Security has been tightened across European capital cities.

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Six of the dead have been identified as German nationals, according to German news agency DPA, citing police. The Polish driver was found dead in the truck's passenger seat. A woman from Italy and another from Israel were missing after the attack, according to DPA.

"We will not let cosmopolitan Berlin be taken by such a cowardly attack, by fear and terror," Berlin Mayor Michael Müller said at a memorial service at the Kaiser Wilhelm Memorial Church on Tuesday evening.

Contributing: Jane Onyanga-Omara in London



