BERLIN (AP) — A Tunisian man detained on suspicion of involvement in last week's Berlin truck attack was released Thursday after investigators determined that he wasn't in contact with the main suspect immediately before the rampage.
The 40-year-old was detained in Berlin on Wednesday. Federal prosecutors said at the time that his telephone number was saved in suspect Anis Amri's cellphone and that they suspected he may have been involved.
Prosecutors' spokeswoman Frauke Koehler said Thursday that investigators had suspected Amri might have sent him a message and a picture over a messenger service shortly before the Dec. 19 attack on a Christmas market.
But "further investigations determined that the man who was provisionally detained isn't this possible contact person of Anis Amri, so he had to be released from custody," Koehler told reporters.
Amri, a 24-year-old Tunisian, is believed to have driven the truck that plowed into the market, killing 12 people. His fingerprints and wallet were found in the truck.
The Islamic State group has claimed responsibility for the attack and released a video showing Amri pledging allegiance to its leader, Abu Bakr al-Baghdadi. Investigators have determined that the video is genuine, Koehler said.
Germany on Dec. 21 released a Europe-wide wanted notice for Amri, who used a string of different names and nationalities. He was killed in a shootout Friday with Italian police in a Milan suburb after they stopped him for a routine identity check.
Prosecutors believe he traveled via the Netherlands and France, Koehler said. In Milan, he was carrying a .22 pistol that he used to shoot a police officer, hitting him in the shoulder.
A bullet found in the truck used in the attack was also from a .22 firearm, but ballistic tests have still to confirm whether it was the same weapon, according to Koehler.
The truck's regular Polish driver was found dead in the cab. Koehler said that a provisional autopsy report shows that he died close to the time of the attack, but it isn't yet possible to give an exact time.
Koehler confirmed German media reports that the truck apparently was slowed by an automatic braking system, bringing it to a standstill after 70 to 80 meters (230 to 260 feet) and preventing worse carnage.
Amri, who had previously spent time in prison in Italy, arrived in Germany in July 2015. German authorities tried this year to deport him to Tunisia after his asylum application was rejected.
Italian investigators are trying to determine whether Amri was tapping a jihadi network in Italy, his port of entry to Europe in early 2011 amid the Arab Spring upheaval.
However, "no particular networks have emerged in Italy," Premier Paolo Gentiloni told reporters in Rome.
Authorities in Rome, meanwhile, seized cellphones during a search of two residences in Rome where Amri stayed in 2015, Italian news agency ANSA reported. One of the apartments is home to a Tunisian currently jailed on a drug dealing conviction.
German authorities had put Amri under covert surveillance for six months earlier this year following a warning from intelligence agencies that he might be planning an attack. The surveillance ended in September after police found no evidence of his alleged plans.
Separately, prosecutors in the western German city of Duisburg said Thursday that they opened a fraud investigation against Amri in April but shelved it in November because his whereabouts were unknown.
Amri was being investigated for receiving asylum-seeker benefits in two different towns, under different identities, for a few days in late 2015.
Colleen Barry in Milan contributed to this report.