BRUSSELS — Belgian prosecutors on Friday revealed new details about the biggest mystery in the Paris attacks: What happened to fugitive Salah Abdeslam after he ditched his car and explosive vest?
After slipping through a police dragnet, they said, he apparently hid out in the same Brussels apartment that served as the killers' bomb factory.
"We found material to make explosives, we found traces of explosives and we found three belts. So you don't have to be Sherlock Holmes to make the right deduction," Belgian Federal Prosecutor Eric Van der Sypt told The Associated Press.
Also discovered during a Dec. 10 police search of the third-floor residence on the Rue Henri Berge: one of 26-year-old Abdeslam's fingerprints, the Federal Prosecutor's Office announced in a statement.
A Brussels native whose older brother, Brahim, was one of the Paris suicide bombers, Abdeslam is believed to have played a key logistical role in the Nov. 13 carnage in which 130 people lost their lives. Islamic State extremists have claimed responsibility for the mass killings.
Early on the morning of Nov. 14, Abdeslam called two friends in Brussels to come fetch him from the French capital.
A French gendarme stopped the three men in their car near the border, but released them. Authorities now believe Abdeslam arrived later that same day at the apartment in the Schaerbeek district of the Belgian capital, eventually was picked up by someone else, "and we lost him," Van der Sypt said.
It's not yet clear when Abdeslam was most recently in the apartment, he said.
Now the target of an international manhunt, Abdeslam's whereabouts remain unknown. "If we knew where he was, we'd catch him," said Van der Sypt. Earlier unconfirmed reports said he was spotted two days after the Paris attacks in Liege in eastern Belgium, heading toward Germany.
Last month, some Belgian tabloids reported he'd been smuggled Nov. 16 out of a hideout in Molenbeek, another Brussels neighborhood where he and other Paris attackers lived, by an accomplice who feigned a household move and hid him inside a piece of furniture.
Van der Sypt said authorities decided to release information about last month's search to dispel inaccuracies published by some media. Refusing to disclose specifics, the prosecutor said evidence acquired in the apartment "has helped us get further in the investigation."
According to the Federal Prosecutor's Office, the residence on a quiet Schaerbeek street flanked on both sides by row houses was rented under a false identity that may have been used by one of the people currently held in Belgium on suspicion of aiding and abetting the Paris attackers.
That person was not identified by Belgian authorities. One of the 10 men arrested, Ali Oulkadi, a welder and restaurant deliveryman from Molenbeek, is suspected of being the person who drove Abdeslam to Schaerbeek from another district of Brussels. Detained Nov. 22, Oulkadi has been charged with participation in the activities of a terrorist group and terrorist murders.
Inside the Rue Henri Berge apartment, three handmade belts were found by police, and "could have been intended for the transport of explosives," the prosecutor's office said.
Traces of TATP, the same highly volatile material that was packed into the suicide vests in November, were also discovered there on a piece of cloth, Van der Sypt said, as well as other material that could be used to manufacture explosives.
He said plastic bottles cut in half and containing an unknown substance were also found and seized, and were being tested by forensic specialists.
The Nov. 13 attacks marked the height of a violent year for France that began with the Jan. 7, 2015, assault on the offices of the Charlie Hebdo satirical newspaper, which was also claimed by the Islamic State group.
Paris was again jolted Thursday when a man wearing a fake explosives vest and wielding a butcher's knife ran up to a police station and was shot to death by officers standing guard.
The Paris prosecutor, Francois Molins, said investigators are unsure of the man's true identity.
Molins told France-Inter radio Friday that the assailant carried a paper marked with the Muslim declaration of faith, an emblem of the Islamic State group and a name, and gave his nationality as Tunisian. Molins said he also had a phone with a German SIM card.
Police are "working on the hypothesis" that the assailant is a man who was involved in a minor 2013 robbery in the southern Var region, according to a French security official who spoke on condition of anonymity because he was not authorized to discuss the case.
The official said that while the fingerprints of the dead attacker matched those of the robbery suspect, who identified himself at the time as Ali Sallah of Casablanca, Morocco, the assailant in Thursday's attack appeared older than 20.
On Friday, Belgian authorities said they were concerned about the possibility of new attacks in their country to mark the anniversary of the Jan. 15, 2015, police raid in the eastern city of Verviers that foiled a suspected plot by Islamic extremists. Two returnees from Syria were killed in that action, and a third arrested.
On Friday, OCAM, the independent agency that evaluates the probability of a violent extremist attack in Belgium, maintained the threat level at 3 on a 4-point scale, signifying such a menace is deemed "possible and likely."
"We obviously take into account these symbolic dates, because they (the extremists) are in search of symbols," Frederic Van Leeuw, Belgium's chief counterterrorism prosecutor, told RTL television.
Associated Press writers Lori Hinnant and Philippe Sotto in Paris and Lorne Cook in Brussels contributed to this report.