The Belgian authorities are looking for a possible accomplice to Mehdi Nemmouche, who has been charged with murdering four people at the Jewish Museum in Brussels last year, the prosecutor's office said Friday.
The prosecutor's office said "we are looking for this person," who has not been identified, when asked to confirm a report in La Derniere Heure daily.
Responding to a request from the prosecutor and examining magistrate, Belgian police last week issued an appeal for witnesses so as to identify a man who appeared on a surveillance camera.
The wanted notice for the man was published in the context of a murder investigation.
On the police's website, it appears next to the wanted notice for Nemmouche, who was arrested in the French port city of Marseille as he got off a bus from Brussels on May 30, six days after the museum attack.
The notices for the unidentified man and Nemmouche also carry the same date, May 24, the day of the attack.
"We confirm that there is a link between the two wanted notices and that we are looking for this person. The investigation will determine whether this person is an accomplice or not," the prosecutor's office said.
The 19-second clip from the surveillance camera shows a man with a shaved head walking on a pavement. A backpack slung over a shoulder, he is wearing a striped T-shirt and jeans.
A second man walking with him is entirely blurred out but La Derniere Heure said he was Nemmouche. During his arrest, French police found a revolver, a Kalashnikov assault rifle and ammunition in his luggage.
Nemmouche had returned months before from Syria where he had been fighting for Islamist extremists.
After being extradited to Belgium, Nemmouche was charged with "murder in a terrorist context" after an Israeli couple, a French woman and a Belgian were shot dead at the museum in central Brussels. Nemmouche has never admitted to being the killer, although recordings reportedly captured him boasting of the attack.
The shooting was the first such attack in Brussels in three decades.
On January 15, Belgian police carried out a series of raids to foil what they said was an imminent Islamist plot to kill police officers. Two suspected terrorists were killed in one of the raids.
Police have so far established no link between the alleged plot and a series of Islamist attacks that killed 17 people in Paris a week earlier.
AFP contributed to this report.