Belgian Suspect in Paris Had Been Target of Strikes on ISIS in Syria

The Belgian man suspected of being the plotter of the Paris terrorist attacks was a target of Western airstrikes on the Islamic State stronghold of Raqqa, Syria, as recently as last month, according to a European security official.

The man, Abdelhamid Abaaoud, 27, a fighter for the Islamic State, is believed to have escaped to Syria after the authorities in January foiled another terrorist plot, which had targeted the eastern Belgian city of Verviers, the official said, speaking on the condition of anonymity to discuss operational details.

The search for Mr. Abaaoud intensified as both French and Russian warplanes pounded Raqqa. Ten French fighter jets, taking off from bases in Jordan and the Persian Gulf, dropped 16 bombs around 1:30 a.m. Paris time on what the French Defense Ministry described as a command center and a training center, both belonging to the Islamic State. Hours later, the Russian military launched cruise missiles and long-range bombers at Raqqa, after Moscow announced that a terrorist bomb brought down a Russian charter jet over the Sinai Peninsula in Egypt on Oct. 31, killing all 224 on board. The Sinai branch of the Islamic State has taken responsibility for that attack.

Across Europe, the search for suspects and clues in the Paris assaults continued.

Federal prosecutors in Belgium on Tuesday charged two Belgian citizens — Hamza Attou, 21, a Brussels native; and Mohamed Amri, 27, who was born in Morocco — with participation in a terrorist activity or organization, in connection with Friday’s attacks. They were among seven men arrested on Saturday; the other five have been released.

Both men live in the Brussels district of Molenbeek, which was a base for Mr. Abaaoud and for two brothers: Ibrahim Abdeslam, who blew himself up inside a restaurant on Friday; and his brother Salah, now the target of a manhunt.

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.

On Tuesday, the Austrian police disclosed 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. Mr. Abdeslam crossed into Austria from Germany in a car with two other men who have not been identified, an Interior Ministry spokesman said. Mr. Abdeslam told the police that he would be spending a few days on vacation in Austria, the spokesman said.

On Tuesday, the European Union took the extraordinary step of invoking an article of the bloc’s Lisbon Treaty that states: “If a member state is the victim of armed aggression on its territory, the other member states shall have towards it an obligation of aid and assistance by all the means in their power.”

A French Army fighter jet at an undisclosed air base on Tuesday. The Defense Ministry said its strikes in Syria destroyed an Islamic State command center and a training center.

Interior Minister Bernard Cazeneuve told France Info radio that the police had conducted 128 raids in France overnight against terrorism suspects.

Mr. Cazeneuve also said that 115,000 police officers and troops had been deployed across the country “to ensure the protection of the French.”

The new details of the hunt for Mr. Abaaoud and the failure of the airstrikes to kill him are the latest evidence of how many of those suspected of having taken part in the Paris attacks were known to the authorities beforehand.

In Washington, Representative Adam B. Schiff of California, the senior Democrat on the House Intelligence Committee, said on Monday that some American officials believed Mr. Abaaoud was still in Syria.

Mr. 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, Mr. 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, Mr. 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.

France remained in a state of emergency on Tuesday, the third and final day of official mourning.

Secretary of State John 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,” Mr. Kerry said before separate meetings with Mr. 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.”

Mr. Kerry reiterated President 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.” At least four Americans were wounded in the attacks on Paris, and one, Nohemi Gonzalez, died.

After meeting with Mr. Hollande, Mr. 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,” Mr. Kerry said. “No one will interrupt the business of the global community, certainly not despicable, cowardly acts of terror.”

By AURELIEN BREEDEN, KATRIN BENNHOLD and KIMIKO DE FREYTAS-TAMURA