An acquaintance of the suspected attacker has been arrested
New details have emerged about the journey that Anis Amri made in the days after he drove a lorry into a Berlin Christmas market.
Police in Belgium have released a CCTV image which shows that Amri (24) arrived at Brussels North railway station on a train from Amsterdam two days after the December 19th attack.
He spent two hours at the station before departing at around 9.00pm. It is thought he then headed to Italy via France.
Amri was killed in a shootout with Italian police in Milan on December 23rd, after officers stopped him for a routine identity check.
The details of his journey following his escape from Berlin come as officials in Germany investigate a second Tunisian man over the attack, which resulted in the deaths of 12 people.
The 26-year-old man had known Amri since the end of 2015, German federal prosecutors said.
Spokeswoman Frauke Koehler said the pair ate dinner together at a Berlin restaurant the night before Amri drove a truck through the market.
Ms Koehler added: "This contact person is a 26-year-old Tunisian. We are investigating him for possible participation in the attack."
Prosecutors believe the man may have been involved, or that he was at least aware of what Amri planned to do.
Police searched his room on Tuesday evening.
While "communications devices" found during the search are still being examined, Ms Koehler said prosecutors do not currently have enough evidence to arrest the man.
Instead, he was detained by Berlin local prosecutors over a separate case, accused of falsely claiming benefits.
Another search has been conducted at the home of Amri's one-time roommate, who is seen as a witness in the case, Ms Koehler said.
Earlier on Wednesday, more details emerged about Amri's actions after the attack.
Police have examined surveillance footage from the Zoologischer Garten station, just a few minutes' walk from the Christmas market.
In the footage, Amri turns towards the camera and appears to show a "tawhid finger", or raised index finger, an Islamic gesture sometimes used by jihadis.
Ms Koehler said the images "suggest that Amri was aware that he was being recorded by this video camera".
Islamic State group has claimed responsibility for the attack.