France pounds ISIS stronghold in Syria

French fighter jets launched their biggest raids in Syria to date targeting the Islamic State's stronghold in Raqqa just two days after the group claimed coordinated attacks in Paris that killed more than 130 people, the defense ministry said.

"The raid ... including 10 fighter jets, was launched simultaneously from the United Arab Emirates and Jordan. Twenty bombs were dropped," the statement said, adding that the mission had taken place this evening.

The operation, carried out in coordination with U.S. forces, struck a command center, recruitment center for jihadists, a munitions depot and a training camp for fighters, it said.

Following Friday's attacks, the US announced that it will expand its intelligence sharing with France via so-called "targeting packages" that will help French warplanes identify ISIS militants in Syria and Iraq, the Wall Street Journal reported.

Sunday's airstrikes signal a major escalation of combat power for the French, who had up until now refrained from launching major airstrikes in Syria.

On Saturday, French President Francois Hollande declared the previous night's attacks "an act of war," and attributed them to the Islamic State.

"It is an act of war that was prepared, organized and planned from abroad, with complicity from the inside, which the investigation will help establish," Hollande said.

In an official statement released in Arabic, English, and French through its various online propaganda platforms, ISIS said its fighters - strapped with suicide-bombing belts and carrying machine guns - carried out the attacks in various locations in the heart of the capital that were carefully studied.

"France and those who follow its path must know that they remain the principle targets of the Islamic State," the statement read.

Seven of the attackers had been killed either by police or by detonating themselves as of Saturday morning. Experts say evidence suggests that some of the assailants might have had training in the Middle East, and investigators believe the attackers were in regular contact with ISIS militants in Syria.

At least one of the attackers believed responsible for the massacre in the Bataclan concert hall, which left 89 people dead, was a 29-year-old French national named Ismael Omar Mostefai who had been on the French government's radar since 2010 for his suspected ties to extremists.

Police say it is likely he crossed into Syria between 2013-2014, where he probably received training by militant groups, The Washington Post reported.

A senior European intelligence official familiar with the case named two other attackers as Ibrahim and Salah Abdeslam, two French-born brothers living in Belgium.

Police are on the hunt for Abdeslam and have issued a warrant for his arrest.