Tunisian authorities have arrested the nephew of Berlin attack suspect Anis Amri and two others linked to him, the Interior Ministry said Saturday.
The three suspects - aged between 18 and 27 - were arrested in a police raid on Friday in Tunisia's central province of Kairouan, where Amri's hometown is located, the ministry said in a statement.
Amri's nephew has confessed that the Berlin attack suspect had asked him to join Daesh and sent him money by post to enable him to travel to Germany, the statement added.
Amri, a 24-year-old who had been the subject of a terrorism investigation while living in Germany as an asylum seeker, was shot dead in Milan early Friday after he shot an officer in the shoulder during a routine police check.
The fact that Amri - who is suspected of having driven a truck into a Berlin Christmas market late Monday, killing 12 people and injuring dozens - was able to flee Germany to France and then Italy has prompted criticism of the investigation.
Germany's top security official has denied charges that authorities bungled the investigation.
"To speak about a failure by the security authorities would be inappropriate," Interior Minister Thomas de Maiziere told Germany's Bild newspaper on Saturday. "However, we will of course analyze the case meticulously and release a corresponding report."
Hundreds of German investigators are now probing how Amri managed to flee the country after the attack, whether he may have had accomplices or a support network that helped him escape, as well as how and when he became radicalized.
Islamic State claimed responsibility for the attack. In a video released by its semi-official Amaq news agency on Friday, a man it claims is Amri pledges allegiance to the head of the group and vows revenge for Muslims.
Amri has been linked by German authorities to Abu Walaa, a Salafist preacher and the suspected head of an organization that provided logistical and financial support to Daesh from western Germany. The Iraqi national was arrested in November.
The 12 victims of the attack include seven Germans, as well as an Italian, a Czech, a Ukrainian, an Israeli and a Polish national believed to be the driver of the truck, Germany's federal criminal police said Saturday.
A spokeswoman for the BKA said that there were no children among those killed in the attack, adding that she could not give further details about the victims due to privacy considerations.
The Italian woman's body was flown to Rome on Saturday, with President Sergio Mattarella and Defence Minister Roberta Pinotti in attendance when the flight landed, Italian news agency ANSA reported, adding that her funeral would take place Monday.
German authorities have said that several of those injured remain in life-threatening condition at Berlin hospitals.
A spokesman for the Berlin police said Saturday that there would be an increased presence of uniformed and plainclothes officers on the streets of the capital over the Christmas holidays.
