PARIS — The fallout from Friday night’s barrage of terrorist violence was felt far and wide throughout France on Saturday. Many in the nation spent a sleepless night glued to TV and online reports detailing the horror of the coordinated assault that left at least 129 people dead and more than 350 wounded from shootings and suicide bomb attacks. Nearly 100 of those injured are in critical condition, officials said.

Eight terrorists were killed, seven of whom were suicide bombers, according to French prosecutors. A total of three groups of extremists mounted the attacks. Authorities are now investigating a fourth band of terrorists who may have fled Paris and may be hiding in Belgium, according to Le Monde newspaper.

One terrorist has been identified as a French citizen in his 30’s, per the national publication. Meanwhile, a Syrian passport was found on the ground at the French stadium, one of the seven sites that was hit by attacks. The passport belongs to a migrant who was registered in Greece in October, per Le Figaro. The names of the terrorists have not yet been unveiled by the media.

Francois Hollande, President of France, declared three days of national mourning at a news conference Saturday. He squarely put the blame for the attacks on ISIS, which has claimed credit for the carnage executed in six attacks over a three-hour period on Friday night. “It is an act of war that was committed by a terrorist army, a jihadist army against France,” a visibly shaken Hollande said.

Movie theaters, museums and other public institutions in the city announced early closings on Saturday on the heels of the shootings and hostage situation that unfolded at one of the city’s most popular concert venues, the Batalcan, on Friday. Disneyland Paris was closed for the day. Sunday’s planned premiere of Steven Spielberg’s “Bridge of Spies” was canceled by 20th Century Fox.

U2 had been scheduled for a concert at Paris’ AccorHotels Arena that was supposed to be telecast live tonight on HBO. But the group hastily canceled the event amid the state of emergency declared by Hollande. It’s just one high-profiie example of the slew of arts, cultural, sporting and community events that have been put on hold as the country deals with the grief and fear provoked by the attacks.

Flowers, candles and other tributes began piling up on Saturday at the site of the attacks, which ranged from the Stade de France sports stadium just outside Paris to two restaurants and the Bataclan concert hall in the heart of the city. Although authorities have advised people to stay home, many are gathering at Place de la Republique to light candles to pay tribute to the victims. Place de la Republique was the site where the Charlie Hebdo unity march began in January after 12 staffers were shot and killed at the satirical magazine.

Canal Plus, France’s largest pay TV network, has axed all entertainment programming this weekend in favor of continuing news coverage of the crisis. TF1 and other national and regional outlets have also been in wall-to-wall coverage mode. TF1 was broadcasting the soccer match between France and Germany that was the target of suicide bombers that killed at least 40 people.

“When it became clear that an attack was unfolding, the commentators of the game announced a special news flash but didn’t clearly say it was an attack because six million people were watching and we didn’t want to stir a wave of panic,” said a TF1 rep.

After interrupting the game, TF1 switched to news programming. Tonight’s regularly scheduled telecast of “Dancing With the Stars” is tabled in favor of an extended newscast, TF1 said.

Discussions are also believed to be under way among French outlets for some kind of TV special paying tribute to the victims and to appeal for peace and calm.

The level of shock, sadness and anger roiling through the country cannot be overstated, observers say.

“People are in shock. It’s like the morning after 9/11,” Laurence Haim, White House correspondent for Canal Plus, told Variety. “You wake up and and now it’s war. It’s there and people feel it is happening.”

Major media conglomerates with operations in France were taking stock of personnel and security concerns. Discovery Communications has a big presence in Paris through its Eurosport cable channels as well as its own Discovery offshoots.

“We are deeply saddened by the events that took place in Paris last night and our prayers go out to the men, women and children involved, their families and friends,” Discovery said in a statement issued Saturday. “We are working with the various authorities and have put in place a number of measures to ensure the security of our employees.”

Cynthia Littleton contributed to this report.