German authorities have named Tunisian man Anis Amri as their prime suspect after a truck drove through a Christmas market on Monday, killing 12 people, Reuters has reported.

In a statement, the German Federal Prosecutor’s Office confirmed its search for Amri, 24. Authorities have offered a €100,000 (£84,000, $104,000) reward for information leading to his arrest.

“Anis AMRI is 178cm tall and weighs about 75kg, has black hair and brown eyes,” the office said in the statement, according to Reuters. “Beware: He could be violent and armed!”

Germany’s interior minister, Thomas de Maizière, said earlier on Wednesday that the German police were collaborating with authorities in Europe’s Schengen states to find Amri. He did acknowledge, however, that Amri may not be the driver behind the attack.