Belgium charged a fifth suspect with terror offenses related to the attacks in Paris earlier this month as Brussels remained under tight security Tuesday.
Belgian authorities issued an international arrest warrant for Mohamed Abrini, who was seen driving a car with fugitive Paris attacks suspect Salah Abdeslam two days before the November 13 atrocities, which left 130 dead and more than 300 wounded.
Authorities said Abrini was seen at a gas station in Ressons on the highway to Paris behind the wheel of the Renault Clio that was used in the attacks.
Abrini is being tracked by both Belgian and French police, the Belgium federal prosecutor's office said Tuesday.
The suspected ringleader of the Paris attacks, Abdalhamid Abaaoud, is also believed to have been planning a suicide attack on the capital's La Defense business district on November 18 or 19, French Prosecutor Francois Molins said Tuesday.
Molins also said cellphone analysis shows Abaaoud appears to have traveled to the attack sites. He said a cellphone believed to be used by Abaaoud shows that the ringleader traveled to the Bataclan concert hall area while the police operation to free hostages was still underway on November 13.
Abaaoud was among three people who died during a November 18 police raid on an apartment in the northern Paris suburb of Saint-Denis. Killed were Abaaoud, a female cousin and one other person who still has not been identified.
On Tuesday, French authorities questioned Jawad Bendaoud, the only person in France facing potential terrorism charges linked to the Paris attacks. He appeared before an anti-terrorism judge in Paris, a judicial official said.
Bendaoud, 29, has been detained since last week for providing lodging to Abaaoud in the Saint-Denis apartment.
Meanwhile, schools and the subway system remained closed Tuesday as the Belgian capital, Brussels, remained under tight security while authorities continued its manhunt for Abdeslam.
Belgian Prime Minister Charles Michel said that because a "serious and imminent threat" still exists, the capital will be on the highest state of alert until at least next week.
Schools to reopen
Michel said he hopes the country can begin returning to normal Wednesday with some schools reopening and trains running in Brussels, which is also the headquarters for the European Union and NATO.
Suspected Paris attacker Abdeslam is being sought after authorities said he evaded a massive manhunt involving raids in Brussels and its suburbs.
After receiving a tip that Abdeslam was in western Germany, police there launched an operation Tuesday in the Minden and Luebbecke areas in North Rhine-Westphalia state.
Police, however, said they found no indication, so far, that Abdeslam is there. The search is ongoing.
On the third day of an unprecedented lockdown of the Belgian capital, officials remain tight-lipped about the biggest security operation mounted in the country since World War Two.
In France, Interior Minister Bernard Cazeneuve told lawmakers 124 people had been handed preliminary charges since a state of emergency was imposed hours after the attacks. He didn't, however, specify what the charges were or if they were linked to the attacks.
Police have executed more more than 1,230 searches, finding 230 weapons, Cazeneuve added.
In Belgium, four other people have been handed terrorism charges since the Paris attacks, officials said.
Paris subway alert
Elsewhere, due to a security alert, several subway stations in central Paris were temporarily closed Tuesday. Trains passed through several stations without stopping, and the Place de la Republique was briefly evacuated but is being reopened, CNN reported.
On Monday, police in the southern Paris suburb of Montrouge were investigating an apparent suicide explosives belt found in a trash bin. A French police official said preliminary analysis of the vest, which lacked a detonator, showed traces of TATP, an explosive used in the Paris attacks.
WATCH: Related video from Brussels
Also, late Monday, the U.S. State Department issued a worldwide travel alert, warning Americans that Islamic State extremists and other terror organizations continue planning attacks "in multiple regions."
The advisory cited recent attacks in Denmark, France, Mali, Nigeria and Turkey, and urged "particular caution" during the coming holiday season.
Meanwhile, businesses in Brussels were starting to feel the impact of the severe security measures. While few question the government's need to protect the public from a potential attack, some shop owners said the shutdown was too extreme.
Esther Willems, assistant manager at the Galler chocolate shop in the heart of Brussels' city center, suspected the alert level had scared away tourists and said he hoped things would start to improve on Wednesday, once the subways and schools begin reopening.
"The (government) measures are a little bit extreme," Willems said. "It's not like terrorists are just walking around the streets here."
Zerif Gan, who runs a souvenir shop opposite the normally swarming Rue de la Bourse, said he didn't have a single customer over the weekend. "It cannot go on like this," he said of the ongoing uncertainty created by the threat level. "We are in the center of Brussels, but even here there is nobody."
Some material for this report came from AP and Reuters.