Three people including the nephew of the Berlin Christmas market attacker Anis Amri have been arrested in Tunisia.
Tunisia's Interior Ministry said Amri - who was shot dead on Friday - had sent his 18-year-old nephew Fedi money to join him in Europe.
Twelve people were killed and dozens more injured in the attack on Monday.
The Tunisian national suspected of carrying out the truck attack that killed 12 people in a Berlin Christmas market appears to have passed through Lyon in France as he fled to Italy, a French judicial source has said.
Video surveillance footage showed Anis Amri at the Lyon-Part-Dieu train station on Thursday, where officials believe he bought a ticket for Chambery, between Lyon and the Italian border.
Amri was shot dead near Milan in Italy in the early hours of Friday after he pulled a gun on police who had asked for his identification papers.
French officials are investigating how the suspect arrived in Lyon after the December 19 attack in Berlin, which has been claimed by the so-called Islamic State.
The funeral for the lorry driver killed in the Berlin Christmas market attack has taken place in his home country of Poland.
Footage has emerged of the final moment before a truck ploughed into a crowd of people at a Christmas market in Berlin.
A man is being hunted by German police after a lorry ploughed into a Berlin Christmas market on Monday, killing 12, but who is the suspect?