PARIS — A dragnet across Europe widened on Tuesday to include a second fugitive suspected to have taken part in the Paris terrorist attacks, as officials tried to make sense of a torrent of emerging intelligence about the planning and execution of the attacks.
The police in France and Belgium continued their pursuit of one fugitive, Salah Abdeslam, 26, a Frenchman who is believed to have escaped to Brussels, while a French official — who was briefed on the investigation but was not authorized to discuss operational details — said Tuesday evening that the authorities were looking for an accomplice, whose identity remained unclear.
Seven attackers died in the assault on Friday night, but it now appears that at least nine took part in or helped facilitate the attacks.
Some of the attackers, who killed 129 people in a closely coordinated series of assaults that lasted three hours, rented a house in a suburb northeast of Paris last week, telling the landlady that they were businessmen from Belgium, according to the French official.
The person suspected of organizing the attacks — a Belgian militant named Abdelhamid Abaaoud, who is 28 or 27 — is believed to be in Syria with fellow Islamic State militants, French and U.S. intelligence officials have concluded.
Early Tuesday, 10 French fighter jets, taking off from bases in Jordan and the Persian Gulf, dropped 16 bombs on what the French Defense Ministry described as an Islamic State command center and training center in the group's self-proclaimed capital of Raqqa, Syria. Hours later, Russia carried out an attack on Raqqa, with cruise missiles and long-range bombers, after acknowledging that a terrorist bomb brought down a Russian jetliner over the Sinai Peninsula in Egypt — a hotbed of Islamic State activity — on Oct. 31.
France, through its defense minister, Jean-Yves Le Drian, took the extraordinary step Tuesday of invoking a European Union treaty that obliges members to help any member that is "the victim of armed aggression on its territory."
President François Hollande took steps to shore up global support for what he has called a war to annihilate the Islamic State, also known as ISIS or ISIL. He met with Secretary of State John Kerry, who expressed sympathy but reiterated the Obama administration's view that the group will not be destroyed until Syria's embattled president, Bashar Assad, leaves power.
Hollande will visit Washington and Moscow next week to meet with President Barack Obama and the Russian president, Vladimir Putin. In Britain, Prime Minister David Cameron told Parliament that the Paris attacks had strengthened the case for intervening against the Islamic State in Syria, a move that Parliament rejected in 2013.
On France's third and final day of national mourning, crowds gathered to light candles and lay flowers at the Place de la République and at makeshift memorials at the sites of the attacks. In the southwestern city of Toulouse, thousands gathered in the central square, waving French flags and singing "La Marseillaise," France's national anthem.
"The terrorists want to erase everything: culture, youth, life, and also history and memory," Hollande said in a speech at a UNESCO conference in Paris.
"You do not fight against terrorism by hiding, by putting your life on hold, by suspending economic, social and cultural life, by banning concerts, theater, sports competitions," he said. "We will not yield to terrorism by suspending our way of life."
Many Parisians and visitors followed his advice, flocking to restaurants, cafes and museums in an effort to carry on with normal life. But the country continued to reel from the attacks, the worst violence on French soil in decades. Officials said that the bodies of 117 of the 129 people killed had been positively identified; 221 of the 352 people injured remained in hospitals, 57 of them in intensive care.
The country remained under a state of emergency, as developments in the investigation emerged in a steady trickle.
In the morning, the authorities seized and towed a black Renault Clio with Belgian license plates in the 18th Arrondissement on the northern edge of Paris, next to the suburb of St.-Denis, where three suicide bombers detonated their explosives during a soccer game at the Stade de France. On Tuesday night, authorities released a photo of one of those bombers — who used a Syrian passport to enter Greece last month, evidently posing as a migrant — and asked for the public's help in identifying him. The passport was probably stolen, and the identity on the passport page — Ahmad al-Mohammad, 25, of Idlib, Syria — may be that of a dead Syrian soldier, the French official said.
Authorities said the car had been seen — it was not clear when, or who drove it — on the A1 highway, which connects the suburbs of Paris with the northeastern city of Lille, about a dozen miles from the Belgian border.
In Belgium, the authorities put the country at its highest alert level. They charged two men — Hamza Attou, 21, a Brussels native, and Mohamed Amri, 27, who was born in Morocco — with participating in a terrorist activity, saying they had driven Abdeslam, the fugitive, from Paris to Brussels.
The two men frequented a bar owned by Abdeslam and his brother Ibrahim, who blew himself up at a restaurant on Friday in one of the attacks. The brothers lived in the Brussels district of Molenbeek, which was also the base for Abaaoud, the Belgian believed to have planned the attacks.
A third brother, Mohamed, who was not involved in the assaults, made a public appeal on Tuesday for Salah Abdeslam to turn himself in.
"We are a family, we are thinking about him, we are wondering where he is, if he is scared, if he is feeding himself," Mohamed Abdeslam told French news channel BFM TV in Brussels. "The best would be for him to surrender, so that the justice system may shed light on this situation."
Salah Abdeslam was stopped at a traffic check in the French town of Cambrai on Saturday morning, as he headed toward the Belgian border, but was waved through after an identity check.
The Austrian police disclosed Tuesday that Salah Abdeslam was also stopped during a routine police check in northern Austria on Sept. 9 — four days after Germany and Austria opened their borders to refugees streaming in via Hungary. Abdeslam crossed into Austria from Germany in a car with two other men who have not been identified, and told police that he would be spending a few days on vacation in Austria, an Interior Ministry spokesman said.
In Washington, Rep. Adam B. Schiff of California, the senior Democrat on the House Intelligence Committee, said Monday that some U.S. officials believed that Abaaoud was still in Syria.
Abaaoud was most likely part of an Islamic State cell that has developed over the past year to help plan, organize and execute terrorist attacks in Europe and particularly in France, Schiff, who receives regular intelligence briefings, said in a telephone interview.
The cell is believed to be led by Abu Mohammed al-Adnani, who also serves as an official spokesman for the Islamic State, a Pentagon official said on Monday.
Even as the contours of the plot and its organizers started to emerge, Schiff warned that much was still unknown about how much of the plot was directed from Syria, and how much autonomy had been left to conspirators in France, Belgium and elsewhere.
"There are some very large missing parts," he said.
Kerry, in a hastily arranged trip to Paris to show solidarity, said the United States and France had no choice but to wage war against the Islamic State, the apocalyptic militant group that purports to have restored a caliphate, or a global Muslim community under a single leader.
"This is just raw terror to set up a caliphate," Kerry said before separate meetings with Hollande and Foreign Minister Laurent Fabius. "This is not a situation where we have a choice. We're not choosing to randomly go to war. We're trying to avoid it, trying to find a better path."
Kerry reiterated Obama's observation, a day earlier, that suicide bombings were impossible to completely prevent.
"If somebody is willing to die — if you want to go die on any given day — unfortunately, you can take some people with you," he said.
At least four Americans were wounded in the attacks on Paris, and one, Nohemi Gonzalez, died.
After meeting with Hollande, Kerry said he would be back in Paris shortly to attend a global climate change conference, scheduled for Nov. 30 to Dec. 11.
"Paris, which knows how to rebound, will do so," Kerry said. "No one will interrupt the business of the global community — certainly not despicable, cowardly acts of terror."
Interior Minister Bernard Cazeneuve told France Info radio that the police had conducted 128 raids in France overnight against terrorism suspects.
Cazeneuve also said that 115,000 police officers and troops had been deployed across the country "to ensure the protection of the French."
In a chilling indication of the extent to which extremist violence has been a persistent problem, authorities revealed on Tuesday that the voice on a recording that claimed responsibility for the attack, on behalf of the Islamic State, was most likely that of Fabien Clain, a well-known French militant.
Clain, 36, has been linked to a deadly 2012 assault on French soldiers and Jewish civilians in southwestern France and to a foiled terrorist plot on the Parisian suburb of Villejuif in April of this year. Like Abaaoud, he is believed to be in Syria now.