Belgian prosecutors have launched a public appeal seeking any information on the “man in hat” suspect in the Brussels Airport suicide bombings that killed 16 people.
Belgian federal prosecutor Eric Van der Sypt said authorities were especially interested in any people who might have filmed or photographed the man.
He was seen at the airport with two suicide bombers before they died in the 22 March attacks.
A subsequent explosion at Brussels’ Maelbeek subway station killed another 16 people the same morning.
Photos released by prosecutors showed the “man in hat” leaving the airport on foot, walking to the nearby town of Zaventem and then into Brussels, where all traces of him were reportedly lost.
The suspect also wore a white jacket but discarded it at some point, prosecutors said.
The appeal for public assistance more than two weeks after the suicide bombings indicated that investigators have hit a standstill.
Three bombers, two at the airport and one in the subway, also died in the attacks, which Islamic State claimed responsibility for.
According to a video reconstitution of the suspect’s itinerary presented to reporters, the man left the Brussels Airport terminal at 7:58am before two other men he was with in the building exploded suitcases laden with explosives.
He passed by a Sheraton hotel, walked through the town of Zaventem, discarded his jacket, and was seen on video footage at Meiser square in north-eastern Brussels at 9:42am. Eight minutes later, sightings of him came to an end.
Belgian authorities are hoping that they or someone finds the discarded light-coloured jacket, saying it could yield precious clues.
Federal prosecutor Thierry Werts also said there had been many people around the hotel when the suspect walked by who may now be overseas, and asked for their assistance as well.
Prosecutors asked “people who might have filmed or taken a photograph of the suspect or think they can provide extra information” to call a special telephone number or to email authorities.
Earlier yesterday, the lawyer for Paris attacks suspect Salah Abdeslam said it will take some weeks before his client can be extradited from Belgium to France.
Sven Mary spoke after a legal hearing on the Belgian-born French citizen’s continuing detention in Belgium.
He said the existing “Belgian arrest warrant must be lifted for (Abdeslam’s) transfer” to France, in accordance with the extradition request.
Mr Mary said before Belgian authorities allow Abdeslam to leave they want to question the 26-year-old about another case – a deadly police raid in the Forest neighbourhood of Brussels days before his arrest.
Abdeslam fled to Belgium after the deadly 13 November attacks on Paris and was arrested on 18 March after four months on the run.
Since his arrest he has been in a prison in the Belgian city of Bruges.
He faces preliminary terrorism charges in France for the Paris attacks, which killed 130 people and left hundreds wounded.