Police have taken into custody the father and brother of a French gunman linked to a string of deadly Paris attacks and are searching their homes, sources say.
The body of the 29-year-old French national was found and identified at the Bataclan music hall where 89 people were shot dead on Friday when three gunmen wearing suicide vests opened fire on spectators in the bloodiest of a string of attacks in Paris blamed on Islamists.
Investigators were also searching the homes of friends and relatives of the Frenchman on Saturday, another source close to the inquiry said.
The father's house is located in the small town of Romilly-sur-Seine, about 130km east of Paris, while his brother's is south of Paris in the Essonne region.
The brother, who is 34, contacted the police on his own initiative and was then taken into custody.
The Frenchman confirmed as one of the attackers was known to police as being close to radical Islam but had never been linked to a terrorism inquiry, Paris prosecutor Francois Molins said on Saturday (local time).
He was identified via a severed fingertip.
Prosecutor Molins said seven gunmen were killed in the attacks, which were the work of three co-ordinated teams. Six of them blew themselves up while one was shot by police, which detonated his suicide vest.
An angry President Francois Hollande has promised a "merciless" response to a wave of attacks by gunmen and bombers across Paris, describing the assault claimed by Islamic State as an act of war against France.
Prosecutors said the co-ordinated assault on restaurants, a concert hall and the national soccer stadium appeared to have been carried out by a multinational team with links to the Middle East and Belgium as well as home-grown French roots.
"This is the Islamic State's way of saying to the French public that if you come and fight your wars in the Middle East, and you fight us down here, we can reach out and touch you at home," security analyst Dr Paul Buchanan told RadioLIVE.
Mr Buchanan says Islamic State's military-like execution of these attacks show a high-level of sophistication.
"Not just because of the multiple targets, the rolling assault…but where you really saw their sophistication was in their operational secrecy."
The Paris public prosecutor said 129 people were killed and 352 wounded, of whom 99 remain in a critical condition. Six attackers blew themselves up and one was shot by police. There may have been an eighth attacker, but this was not confirmed.
In the worst carnage, gunmen systematically killed at least 89 people at a rock concert by an American band at the Bataclan music hall before blowing themselves up as anti-terrorist commandos launched an assault, officials said.
About 40 people were killed in five other attacks in the Paris region, including a double suicide bombing outside the Stade de France stadium, where Hollande and the German foreign minister were watching a soccer game.
The mass bloodshed came as France, a founder member of the US-led coalition waging air strikes against Islamic State in Syria and Iraq, was on high alert for terrorist attack.
It was the worst such attack in Europe since the Madrid train bombings of 2004, in which 191 died.
Hollande said the attacks were organised from abroad by Islamic State, with internal help.
Three people were arrested in Belgium as part of an anti-terrorism probe centred on a Belgian hired car found near the site of one of the Paris attacks, Belgian prosecutors said.
Sources close to the inquiry said one of the dead gunmen was French with ties to Islamist militants and had been under surveillance by the security services.
The holder of a Syrian passport found near the body of one suicide bombers passed though the Greek island of Leros in October, a Greek minister said.
A Greek police source said the man had arrived in Leros with 69 refugees, where he was registered and had his fingerprints taken.
"Faced with war, the country must take appropriate action," Hollande said in a solemn address after an emergency meeting of security chiefs. He announced three days of national mourning.
Flags flew at half-mast, cinemas, theatres and other places of entertainment were closed, although schools and universities will reopen as normal on Monday.
"France will be merciless towards these barbarians from Daesh," Hollande said, using an Arab acronym for Islamic State.
In its claim of responsibility, Islamic State said the attacks were a response to France's military campaign.
It also distributed an undated video in which a bearded militant warned in Arabic: "As long as you keep bombing you will not live in peace. You will even fear travelling to the market."
Sylvestre, a young man who was at the Stade de France when bombs went off there, said he was saved by his mobile phone, which he was holding to his ear when a metal bolt hit it.
France has been on high alert since Islamist gunmen attacked the satirical weekly Charlie Hebdo and a kosher supermarket in January, killing 18 people.
British police said the evacuation of London's Gatwick Airport on Saturday was connected to the discovery of a possible firearm in a bin and a 41-year-old man from France was arrested.
The Eiffel Tower will be closed indefinitely following the wave of deadly attacks in Paris, the iconic landmark's operator says.
The company decided to close the monument - normally visited by up to 20,000 people a day - after Friday's attacks which claimed at least 128 lives, a spokeswoman told AFP.
It will remain closed "until further notice," she added.
France plans to go ahead with a major global climate change summit in Paris at the end of the month, despite the wave of dead attacks.
The French government says the summit involving nearly 120 world leaders will be held because it's an essential meeting for humanity.
The US says President Barack Obama will be attending.
Loic Wiels could feel the bodies hitting the floor around him at a Paris music hall where a team of assailants opened fire in one of France's deadliest terror attacks.
The bullets whizzed so close, he was hit by the wood splinters they sent flying. And under his feet he could feel the blood that had poured out of the wounded and the dead.
Wiels is a survivor of Friday's assault on the Bataclan concert venue who recounted to AFP how he survived. At least 82 other people there were killed.
Just an hour prior Wiels had felt lucky to be among the crowd at the venue in eastern Paris. He had managed to get a ticket at the last minute for the Eagles of Death Metal concert, which was sold out.
In the packed hall, which can hold up to 1500 spectators, the rock group had been playing for about 45 minutes when the explosions rang out.
Someone in the audience joked: "It's firecrackers."
"I turn around and I see two guys with Kalashnikovs. They were dressed normally: jeans and sneakers. At first I thought they were shooting in the air. Then I saw people falling over," said Sylvain Raballant, 42.
Everyone that was in the pit, like Wiels and Raballant, hit the floor.
"I saw three attackers, two of them clearly. One looked like a young guy, with a three-day beard. The other was closely shaved, wearing small eye glasses and some kind of yellow beret," said Wiels.
Wiels, 33, is now struck by the "incomprehension in the room. I felt the blood on the floor, the shockwaves of the people falling around me. I got hit with woodchips sent flying by the bullets, but in the balcony nobody realised what was happening."
"They fired into the crowd and people tried to escape but the attackers said: 'If you move, we'll kill you,'" said Philippe, 35.
As the audience gradually understood they were caught in a siege, they tried to make themselves as invisible as possible.
But mobile phones were ringing, quickly followed by shooting. It seemed like every 15 seconds there was another shot.
Raballant saw people getting up and trying to escape and decided to do the same. But a fresh burst of gunfire sent him back to the floor with his "head in his hands, near the sound board."
"I couldn't move anymore. I tried not to even breathe. Next to me, there was a drunk guy who kept saying 'We're all going to die.' A couple of us whispered for him to shut up. There were also people who were moaning ... it was horrible," Raballant added.
Anthony, another survivor, said the fact that he was at the back of the room saved his life.
The moving crowd knocked him to the floor.
When he lifted his head, after a moment that lasted "between 30 seconds and 20 minutes...", he saw "a bearded guy, no mask, a gun in his hand," who was shooting methodically.
"I was waiting for the fatal shot," said Anthony.
"And then somebody yelled that they (attackers) were gone, everybody wanted to get out. I slipped in a pool of thick blood. We crawled, we climbed over people."
When Raballant saw the police he ran toward the bar, his hands on his head so as to not be taken for a shooter.
In the meantime, Wiels and Philippe, seizing the moment when the attackers went upstairs, rushed towards the exits.
"From the balcony they started shooting into the pit. When they backed up to reload I got up and I ran, I ran to the exit and I didn't stop until the Metro," said Philippe.
Heavily-armed police have stormed the luxurious Pullman Hotel on Avenue de Suffren near Paris' Eiffel Tower, but a French Interior Ministry spokesperson has said it was a false alarm, according to Sky News.
Police searched room-to-room through the Pullman Hotel before the raid was called off.
The area around the tower and the surrounding Champ de Mars park, as well as a Metro station, continue to have strong police presence.
Security in major cities across Europe and the US is being ramped up in the wake of the Paris attacks.
The suicide bombing outside the stadium hosting a France-Germany match attended by President Francois Hollande has prompted American football to react.
Security services in at least three European countries have detained suspects believed to be linked.
People have been detained in France, Germany and Belgium while an arrest in Britain may also be connected.
AFP / RadioLIVE / 3 News