Explosive belt found in area where Paris attack suspect was traced
An explosive belt has been found in the southern Paris suburb of Montrouge, French police said.
An official said the belt - without a detonator - was found by a street cleaner in a pile of rubble.
Police are analysing the belt to see if it might have been used in the November 13 attacks that killed 130 people, an official for the judicial police said.
They said the explosive belt was found in the place where Abdeslam's mobile phone was operating on the day of the Paris attacks.
Meanwhile, Belgian prime minister Charles Michel has said that the alert level in Brussels will remain at the highest rating for the time being, although schools and the capital's subway will begin to reopen on Wednesday.
Mr Michel told a news conference: "The threat is imminent. We ask our population to stay calm."
Belgian authorities earlier charged a fourth suspect with terrorism offences after the arrests of 16 people on Sunday.
The federal prosecutor said in a statement that the suspect, who was not identified, was charged with "participation in the activities of a terrorist group and a terrorist attack", referring to the November 13 assault on Paris.They said the explosive belt was found in the place where Abdeslam's mobile phone was operating on the day of the Paris attacks.
Authorities charged three others with similar offences last week.
The other 15 people detained on Sunday evening have been released.
Raids across the Belgian capital on Sunday capped a tense day with hundreds of troops patrolling the streets and authorities hunting suspected extremists, including Salah Abdeslam, a fugitive since being named as a key suspect in the Paris attacks.
The Belgian government chose to keep Brussels on the highest state of alert into the start of the working week after what it described as a "serious and imminent" threat.
Federal prosecutor Eric Van Der Sypt said that 19 raids were carried out on Sunday in Molenbeek - home to many of the Paris attackers - and other boroughs of Brussels, while there were three raids in Charleroi.
Abdeslam was not among those arrested. Mr Van Der Sypt added that no firearms or explosives were found in the raids.
Belgian interior minister Jan Jambon said Abdeslam "must have a lot of support on our territory. That's why all these searches being conducted at the moment are important".
In one incident, police fired two shots at a car that approached them as they searched a snack bar in Molenbeek, Mr Van Der Sypt said.
The vehicle escaped but was stopped later in Brussels, and a wounded person inside was arrested.
Several of the Paris attackers lived in Brussels, including Abdelhamid Abaaoud, the plot's orchestrator who was killed on Wednesday in a stand-off with French police.
Belgium said it will maintain its level of security measures to contain a possible attack at least until Monday.
Mr Michel told reporters that the rest of the nation would stay at the second-highest level.
He said: "We do our utmost to keep the situation under control."