Berlin truck attacker used at least 14 names: German police

Anis Amri, shot dead by Italian police in Milan on Dec. 23, had been marked as a potential threat by authorities in the western federal state of North Rhine-Westphalia (NRW)in February 2016, some six months after he arrived in Germany and applied for asylum.

"He acted in a conspiratorial manner and used various personalities," Dieter Schuermann, head of the NRW Criminal Police Unit, told the regional parliament during a briefing.

The 24-year-old divided his time between NRW and Berlin, where intelligence officials also classified him as a potential threat. But there was a consensus among security officials that he posed no concrete threat, Schuermann said.

An investigation into the attack is focusing on whether Amri had any accomplices.

Police arrested another Tunisian man in Berlin this week, who prosecutors say had dinner with Amri at an Arab restaurant in the capital one day before the attack on Dec. 19.