constitutional amendments to fight potential terrorists at home and for an aggressive effort to eradicate the Islamic State abroad.His call to arms France is at war, he said at the opening of his remarks to a joint session of Parliament came as security forces in France and Belgium zeroed inon a suspect they said was the architect of the assault that killed 129 people Friday night in Paris. The suspect, a 27-year-old Belgian, has fought for the Islamic State in Syria and has been linked to other terrorist attacks.Mr. Hollande spoke after the French police raided homes and other sites across the country in an effort to head off possible further attacks and as the authorities in Belgium hunted for a suspected assailant in Fridays attacks.Continue reading the main storyRelated CoverageAfter Paris Attacks, C.I.A. Director Rekindles Debate Over SurveillanceNOV.16, 2015Syrians arriving on the Greek island of Lesbos in July. President Obamas planwould resettle 10,000 Syrian refugees.G.O.P. Governors Vow to Close Doors to Syrian RefugeesNOV. 16, 2015Suicide bombers killed 43 people in a busy district of Beirut, Lebanon, on Nov. 12. The Islamic State claimed responsibility.Where ISIS Claims It Has Struck, and Why NOV. 16, 2015Obama Says Strategy to Fight ISIS Will SucceedNOV. 16, 2015Attackers Possible Link to Migrant Trail Heightens Security FearsNOV. 14, 2015France Strikes ISIS Targets in Syria in Retaliation for AttacksNOV. 15, 2015Belgian security forces conducted an operation in the Molenbeek district ofBrussels on Monday.How Belgium Became Home to Recent Terror PlotsNOV. 15, 2015Mr. Hollande called for quick action by Parliament on new legislation that wouldgive the government more flexibility to conduct police raids without a warrantand place people under house arrest. He said he would seek court advice on broader surveillance powers. And he called for amendments that would enable the stateto take exceptional security measures without having to resort to the most drastic options currently in the Constitution.PhotoAbdelhamid Abaaoud, a 27-year-old Belgian man who has fought with the Islamic State in Syria. Credit Militant Website, via Agence France-Presse Getty ImagesMr. Hollande is also seeking to extend the current state of emergency for threemonths and let the government strip the citizenship of French natives who are convicted of terrorism and hold a second passport.Our democracy has prevailed over much more formidable opponents than these cowardly assassins, Mr. Hollande said a day after France conducted airstrikes against the Syrian city of Raqqa, the self-proclaimed capital of the Islamic State. It was the countrys most intense military strike yet against the radical group, whichhas claimed responsibility for the attacks in Paris.The French leader said he would meet soon with President Obama and President Vladimir V. Putin of Russia in an effort to settle on a united campaign to wipe outthe Islamic State, also known as ISIS or ISIL.Terrorism will not destroy the republic, because it is the republic that will destroy it, he said.Paris Attacks By THE ASSOCIATED PRESS 2:35Brother of Paris Suspect Speaks OutContinue reading the main storyVideoBrother of Paris Suspect Speaks OutMohamed Abdeslam, a brother of two men who helped carry out Friday s terrorist attacks in Paris, said on Monday that neither he nor his family could have imagined his brothers would be involved. By THE ASSOCIATED PRESS on Publish Date November 16, 2015. Photo by Benoit De Freine/Reuters. Watch in Times Video embedThree days after the attacks on a soccer stadium, a concert hall and numerous bars and cafes, French and Belgian security services were focused on the radical jihadist they believe was the leader of the plot, Abdelhamid Abaaoud. He is amongthe most prominent Islamic State fighters to have come out of Belgium.A French official briefed on the investigation, who spoke on the condition of anonymity because he was not authorized to discuss operational details, said Mr. Abaaoud had mentioned plans to attack a concert hall to a French citizen who returned from Syria.Mr. Abaaoud, this official said, had also been in contact with Ismal Omar Mostefa,one of the Paris attackers. Mr. Abaaoud also knew another attacker, Ibrahim Abdeslam; they were tried together in 2010 in Belgium for a minor offense.Attacks in ParisComplete coverage of the shootings across Paris, Europes worst terrorist attack in 11 years.Paris Attacks Complicate Europes Already Strained Border ControlsNOV 16Where ISIS Claims It Has Struck, and WhyNOV 16Waiter Killed in Paris Attacks Is Remembered as a Bon VivantNOV 16In Suspects Brussels Neighborhood, a History of Petty Crimes and Missed ChancesNOV 16Parties Split on Response but United Behind FranceNOV 16See More Mr. Hollande said the attacks had been planned in Syria, organized in Belgium, perpetrated on our soil with French complicity.PhotoSalah Abdeslam. Credit French Police, via Agence France-Presse Getty ImagesThe French authorities said Monday that they had conducted 168 raids across thecountry in an effort to root out possible terrorist threats. The raids extendedfrom the Paris region to the major cities of Lille, Lyon, Marseille and Toulouse, they said. They also said they had arrested 23 people and detained 104 othersunder house arrest.But a Frenchman believed to be involved in the Paris attacks, Salah Abdeslam, 26, a brother of Ibrahim Abdeslam, remained at large, eluding a series of raids conducted by the authorities in Molenbeek, the working-class Brussels neighborhoodwhere the brothers lived.A third brother, Mohamed, and four other men who had been detained in Belgium were released on Monday. At a news conference in Brussels, Mohamed said he did notknow Salahs whereabouts and added, My parents are under shock and have not yet grasped what has happened.The man believed to be the architect of the plot, Mr. Abaaoud, who traveled to Syria last year and even persuaded his 13-year-old brother to join him there, isfrom the same neighborhood, Molenbeek, as the Abdeslam brothers.Continue reading the main storyHow Belgium Became Home to Recent Terror PlotsSeveral recent terrorism cases in Europe have had some connection to Belgium.Mr. Abaaoud was already a suspect, according to officials and local news reports, in a failed terrorist plot in Belgium in January and an attempt in August to gun down passengers on a high-speed train to Paris from Brussels. An intelligenceofficial said the authorities feared he might be in Europe.In Washington, Representative Adam B. Schiff of California, the senior Democraton the House Intelligence Committee, said some American officials suspected thatMr. Abaaoud might still be in Syria. Mr. Abaaoud was most likely part of an Islamic State cell that has developed over the past year to help plan, organize andexecute terrorist attacks in Europe, particularly in France, Mr. Schiff said ina telephone interview.The cell is believed to be led by Abu Mohammed al-Adnani, who serves as an official spokesman for the Islamic State, a Defense Department official said Monday.Mr. Schiff warned that much was still unknown about how much of the plot had been directed from Syria and how much autonomy had been left to conspirators.Continue reading the main storyLatest Updates7hFrances Soccer Team to Play for National Unity and Attack Victims8hA Commenters Ode to Paris Takes Off in France9hEvery Time a Catastrophe Strikes, Bogus Tweets AboundSee All UpdatesAt noon, France observed a moment of silence in honor of the victims of the attack, which wounded about 350 people, in addition to the 129 killed. The Mtro and cars stopped and crowds gathered at a makeshift memorial at the Place de la Rpublique and at the Eiffel Tower. Mr. Hollande stood with students at the Sorbonne. Many recited the national anthem, La Marseillaise, after the moment passed. In other cities Delhi; Doha, Qatar; and Dublin crowds gathered at French embassies to pay their respects.As France observed its second of three days of national mourning, the authorities in France and Belgium raced to track down suspects and chase leads.At one house in the Rhne department in the southeast, around Lyon, the police found a Kalashnikov rifle, three pistols, ammunition and bulletproof vests. Officers then obtained a warrant to search the home of the parents of a man who lived in the house, where they found several automatic pistols, ammunition, police armbands, military clothing and a rocket launcher.Prime Minister Manuel Valls and Interior Minister Bernard Cazeneuve promised tokeep up the search. We are using all the possibilities given to us by the state of emergency, that is to say administrative raids, 24 hours a day, Mr. Valls said.He vowed to keep intense pressure on radical Islamism, Salafist groups, all those who preach hatred of the Republic.Paris Attacks By THE ASSOCIATED PRESS 00:43Hollande Says France Is at WarContinue reading the main storyVideoHollande Says France Is at WarPresident Franois Hollande of France gave a rare speech to lawmakers gathered atthe palace of Versailles. By THE ASSOCIATED PRESS on Publish Date November 16, 2015. Photo by Pool photo by Philippe Wojazer. Watch in Times Video embedThe authorities also confirmed on Monday that one of the attackers entered Europe through Greece on a Syrian passport last month, posing as a migrant.Continue reading the main storyRecent CommentsAlan Lockett 9 minutes agoLeaving aside the Paris attacks, why does no one ask the obvious questions: Where does ISIS get the money and materiel to wage simultaneous...michael 21 minutes agoSad to see the words of Mr. Hollande, sadder still to imagine Paris going the way of NYC after 911. Bush grandstanded on our rubble and...Peter Zenger 35 minutes agoThe lack of imagination on the part of the Western Powers in dealing with the situation in the Middle East is staggering.No matter what...See All Comments Write a commentThe man was identified on his passport found at the soccer stadium north of Paris where he blew himself up Friday night as Ahmad al-Mohammad, 25, a native of Idlib, Syria. The holder of the passport passed through the Greek island of Leroson Oct. 3 and the Serbian border town of Presovo on Oct. 7, according to Greek and Serbian officials. It remained unclear whether the passport was authentic.All told, at least four French citizens were among the seven attackers: IbrahimAbdeslam; Mr. Mostefa, who met with the man suspected of planning the attacks; and two men identified on Monday as Samy Amimour, 28, a Paris native who lived inthe suburb of Drancy, and Bilal Hadfi, 20, who lived in Brussels.Mr. Amimour was known to the French authorities,2012 with terrorist conspiracy, according to ther judicial supervision but violated the terms ofting the authorities to put out an internationalContinue reading the main storyGraphicThree Hours of Terror in Paris, Moment by Momenthaving been charged in Octoberauthorities. He was placed undethat supervision in 2013, promparrest warrant.Many of the attacks were just minutes apart.OPEN GraphicLast December, the French newspaper Le Monde interviewed Mr. Amimours father it did not identify him by name at the time who had gone to Syria to try to bring back his son. Three members of the Amimour family were detained on Monday.Turkey confirmed on Monday that Mr. Mostefa, 29, entered Turkey in 2013, but it said that there is no record of him leaving the country.A Turkish official, speaking on the condition of anonymity, said that the government flagged Mr. Mostefa twice in December and in June but that we have, however,not heard back from France on the matter.He continued, It wasceived an informationded that this is notdo better at sharingonly after the Paris attacks that the Turkish authorities rerequest about Ismal Omar Mostefa from France. The official ada time to play the blame game, but that governments needed tointelligence to prevent terrorism.The United States has provided logistical support for the French airstrikes in Syria, but Mr. Obama on Monday again ruled out a ground intervention.Lets assume that we were to send 50,000 troops into Syria, he said at a gathering of leaders of the Group of 20 industrial and emerging-market economies in Antalya, Turkey. What happens when theres a terrorist attack generated from Yemen? Do wethen send troops into there? Or Libya, perhaps?Elsewhere in Europe, the authorities tightened security. Britain announced Monday that it would pay for an additional 1,900 intelligence officers, and review aviation security.In Washington, John O. Brennan, the director of the Central Intelligence Agency,said Monday that the Paris attacks and the crash of a Russian jet over the Sinai Peninsula bore the hallmarks of the Islamic State.Speaking at the Center for Strategic and International Studies, Mr. Brennan called the group an association of murderous sociopaths that is not going to content itself with violence inside the Syrian and Iraqi borders.Wading into the debate over surveillance, privacy and encryption, Mr. Brennan said he hoped the Paris attacks would be a wake-up call, adding that hand-wringing hadweakened the ability of Western intelligence services to prevent attacks.