What we know about Tunisian suspect in Berlin attack

A Europe-wide manhunt for the truck driver who is suspected in Monday's fatal Christmas market attack in Berlin is underway. Here's what we know about the Tunisian man believed to be linked to the rampage that killed 12 people:

Who is the Tunisian suspect? 

Anis Amri, who turns 24 on Thursday, became a suspect after investigators discovered a wallet with his identity documents in the truck used in Monday's attack. 

Amri, who entered Germany last year, was the subject of a terrorism investigation in the country earlier this year. He was not deported in July even though his bid for asylum had been rejected because he did not have valid identity papers, said  Ralf Jaeger, the interior minister of western North Rhine-Westphalia state.

Germany hunts 'armed' Tunisian suspect in truck attack

On Wednesday, German media published photos of Amri and federal prosecutors issued a public appeal for information about him. The notice said he could be "violent and armed" and offered a reward of up to 100,000 euros ($104,000). 

Amri has at times used at least six different names and three different nationalities, according to a different arrest warrant from Germany obtained by the Associated Press. Amri is said to be of average height and weight, with black hair and brown eyes. 

His birthdate is listed in the warrant as Dec. 22, 1992, according to the AP. 

German lawmaker Stephan Mayer said after being briefed by security officials Wednesday that Amri is thought to have links to Islamic extremists.

When did Amri arrive in Germany? 

He came to Germany in July 2015 and has lived in three German regions since February, mainly in Berlin, according to Jaeger. 

After Christmas market attack, Berlin shaken but still stoic

Was he being investigated before the attack?

Yes. State prosecutors told the AP they had launched an investigation of Amri on March 14 after a tip from federal security agencies. The tip said Amri could be planning a break-in to buy automatic weapons for an attack. Surveillance showed that Amri was involved in drug dealing in a Berlin park and a bar fight, but did not confirm the initial tip. The investigation was called off in September. 

Has Amri been identified by the Islamic State? 

No. The Islamic State did not name Amri when it said Tuesday that a "soldier" committed the deadly attack. 

No evidence has emerged establishing a connection to the militant group, which has staged and inspired assaults across Europe and the United States.