PARIS — France bombed the Syrian city of Raqqa on Sunday night, its most aggressive strike against the Islamic State group it blames for killing 129 people in a string of terrorist attacks across Paris only two days before.
President François Hollande, who vowed to be “unforgiving with the barbarians” of the Islamic State after the carnage in Paris, decided on the airstrikes in a meeting with his national security team on Saturday, officials said.
While France has been conducting scores of airstrikes against the Islamic State in Iraq, it had been bombing inside Syria only sparingly, wary of inadvertently strengthening the hand of President Bashar al-Assad by killing his enemies.
But after militants with AK-47 rifles and suicide explosives vests shattered the peaceful revelry of Paris on Friday night, killing dozens of civilians in restaurants and at a concert hall, France seemed intent on sending a clear message of its determination to curb the Islamic State and its ability to carry out attacks outside the territory it controls.
The French Defense Ministry said in a statement that the air raid, coordinated with American forces, was led by 12 French aircraft, including 10 fighter jets, and had destroyed two Islamic State targets in Raqqa, the radical group’s self-proclaimed capital.
The United States provided French officials with information to help them strike Islamic State targets in Syria, known as “strike packages,” American officials said.
Initial reports from activists on the ground in Raqqa, which could not be verified independently, said that hospitals had not reported any civilian casualties. Yet they also said the targeted sites included clinics, a museum and other buildings in an urban area, leaving the full extent of the damage unknown.
The French military response capped another tense day in the wake of the attacks across Paris on Friday night. The authorities hunted for an eighth suspect believed to be on the loose, while seeking to piece together how the assailants got the training, weapons and explosives they used.
President Obama and other world leaders, including President Vladimir V. Putin of Russia, gathered at a summit meeting in Turkey, grappling with how to respond to the Islamic State, the civil war in Syria and the mass emigration from the region toward Europe.
Paris remained jittery all day, and early in the evening unfounded reports of gunfire prompted an evacuation of the Place de la République, in the heart of the city.
The revelations that at least four French citizens were involved in the attacks — three brothers and a man who lived around Chartres, about 60 miles southwest of Paris — seemed certain to exacerbate longstanding fears in France about the place of Muslim immigrants and converts in French society. Even before the latest violence, the nation was still reeling from a smaller set of deadly attacks on the satirical newspaper Charlie Hebdo, at a kosher grocery and against a police officer only 10 months earlier.
The French airstrikes on Raqqa began at 7:50 p.m. Paris time, first taking aim at an Islamic State “command post, jihadist recruitment center and weapons and ammunition depot,” the Defense Ministry said. The second target, it said, was a “terrorist training camp.”
Warplanes continued to hover over the city close to midnight, according to residents and activist groups. Residents have seen the city bombed by Syrian, American and Russian warplanes. They have been terrorized by public executions by the Islamic State. Now they are wary of yet another power arriving to pummel the city.
Khaled al-Homsi, an antigovernment activist from Palmyra, who uses a nom de guerre for his safety and is the nephew of an archaeologist who was beheaded by Islamic State fighters, issued a plea on Twitter to France, saying not all of the city’s residents were Islamic State members and urging caution for the safety of civilians.