French PM: New attacks 'being prepared' against France, Europe

French Prime Minister Manuel Valls said Monday that authorities believe new terror attacks are being planned in France and in other European countries following the carnage in Paris.

"We know that operations were being prepared and are still being prepared, not only against France but other European countries too," he said.

French police reportedly carried out 168 raids on suspected "radicals" over Sunday night, leaving 104 people under house arrest, Reuters reported on Monday.

Thirteen raids were carried out in the southeastern French city of Lyon, leading to five arrests and the seizure of a rocket launcher, a Kalashnikov assault rifle, bulletproof vests and handguns, local police said.

Also Monday, raids were reported in the Molenbeek suburb of Brussels, where at least two of the suspected attackers were thought to have been living. 

With a manhunt under way for suspects across Europe, French police released a photograph of a "dangerous" suspect also wanted in Belgium, where Friday's bloodbath may have been planned.

France prepared to fall silent at noon Monday to mourn victims of the Paris attacks after the country's warplanes pounded the Syrian stronghold of Islamic State, the militant group that has claimed responsibility for the slaughter.  The EU has called on all member states to respect the minute's silence at midday (1100 GMT). In the US, the Stars and Stripes will fly at half-mast at the White House until sunset on Thursday.

President Francois Hollande will observe the silence at the Sorbonne University, in recognition of the large toll of young people among the 129 dead. Another 352 were injured, scores of them seriously.

Despite a state of emergency, schools were to reopen Monday morning, with museums, theatres and other cultural centres following at 1:00 pm after being shut in the wake of the attacks.

Warplanes hit Raqqa 

The attack by French warplanes on Islamic State's Syrian stronghold Sunday was the nation's first retaliation against the militants. Hollande has denounced the Paris attacks as an "act of war" and vowed to hit back against IS "without mercy".

The raid destroyed an IS command post, a recruitment centre, a munitions depot and a "terrorist" training camp in Raqqa, the defence ministry said.

The operation, coordinated with US forces, was carried out by a dozen aircraft that took off from Jordan and the United Arab Emirates, it said.

"There were at least 36 explosions overnight in Raqqa city, some caused by air strikes and some by weapons and explosives detonating after being hit," said Rami Abdel Rahman, director of the Syrian Observatory for Human Rights.

"The blasts shook the entire city. There were strikes on both the north and south of Raqa," he told AFP.

Abdel Rahman said the strikes were believed to have been carried out by French aircraft.

Among the targets hit was Brigade 17, a military encampment including weapons stores and a training facility.

The Britain-based monitor could not immediately confirm any casualties in the strikes, which come after IS claimed responsibility for attacks in Paris.

"IS has imposed a security alert on the city, and it is difficult to confirm information about casualties from hospitals there," Abdel Rahman said.

Belgian connection

French police meanwhile said they were seeking 26-year-old Salah Abdeslam, who is said to be one of three brothers linked to the slaughter.

He is believed to be either on the run or one of the gunmen who died during the attacks, security sources said. He lived in Brussels, in the rundown immigrant neighbourhood of Molenbeek, where police have made several arrests.

The attacks "were prepared abroad and involved a team situated in Belgian territory and who may have benefited from ... complicity in France," French Interior Minister Bernard Cazeneuve said after talks Sunday with his Belgian counterpart, Jan Jambon.

"We are determined to act together... to dismantle the [jihadists'] networks," he said.

As the investigation spread across Europe, police carried out raids in Bobigny, in the northern suburbs of Paris, Sunday evening.

Prosecutors said they believed three groups of attackers were involved in the carnage, and they have not ruled out that one or more assailants may still be at large.

World leaders on Sunday denounced terrorism at a heavily guarded G20 summit in Turkey and observed a minute's silence for those killed.

In an outpouring of solidarity, more emotional vigils were held across the globe over the weekend, and buildings and monuments  in many capitals were illuminated in the red, white and blue of the French national flag.

In Rome, the lights of the Trevi Fountain and the Colosseum were turned off Sunday night in a silent tribute.

And in a striking gesture, the Great Pyramid in Egypt was bathed in French, Lebanese and Russian colours in homage to the victims in Paris as well as those in this month's Beirut bombings and Sinai plane crash.