France has declared a state of emergency and people in Paris are being told to stay at home after at least 129 people were killed in six co-ordinated attacks across the capital.

Around 40 people died in shootings and bombings at bars, restaurants and a stadium in the capital - more than 80 are thought to have been killed at the Bataclan concert hall.

Out of 300 injured victims, 80 people are said to be in a critical condition after the violence, which French President Francois Hollande has described as an "act of war" by Islamic State .

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IS said the near-simultaneous attacks were a response to insults of the Prophet Muhammed and French airstrikes in IS territory.

The extremist group's statement warned the attacks were "only the start of the storm".

Eight attackers were killed - seven of them in suicide blasts.

Police officials say a Syrian passport was found next to the body of a suicide bomber at the Stade de France stadium, and reports in France say a suspicious black car with Belgian plates was seen near the Bataclan.

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Security at venues across the city is being stepped up, the military has been deployed around the capital and police are hunting possible accomplices - officials say they cannot rule out the possibility more people were involved.

Mr Hollande, who described Friday night's attacks as "a horror", has declared three days of mourning and said: "France was attacked in a cowardly way.

"France will be unbreakable in face of these attacks."

Twitter accounts linked to jihadists have been celebrating the attacks, which are the deadliest in Europe since the Madrid bombings of 2004.

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The scene of the worst carnage was the Bataclan music venue in the city's east.

Three gunmen took dozens of people hostage after first using assault rifles to spray cafes near the building with bullets.

A short time later, elite police commandos launched a dramatic assault on the theatre , but they were unable to save all the hostages.

One witness told French radio they heard the attackers yell "Allahu Akbar" - God is great in Arabic - as they started their killing spree.

All three attackers died at the venue - two detonated explosives, while the third was killed in the police raid.

Around 1,000 people were believed to be there to watch American band Eagles of Death Metal.

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North of the venue, a gunman killed at least 11 people at a Cambodian restaurant and a nearby bar in the 10th arrondissement - not far from the offices of Charlie Hebdo.

Eighteen people sitting at outdoor terraces were also killed on the Boulevard de Charonne in the 11th arrondissement.

Another five people died on Rue de la Fontaine au Roi in the same district.

The victims were reportedly at a pizza restaurant when they were killed.

Around the same time, three bombings, including two suicide attacks, occurred near the Stade de France stadium, where the national football team had been playing Germany in a friendly match.

Two of the blasts happened at entrances to the stadium and another at a nearby McDonald's restaurant.

Three people were killed, according to a police union official.

Mr Hollande was inside the stadium at the time, but rushed to the interior ministry.

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The injured are being treated at several hospitals in the city - more than 50 have been discharged so far.

Residents of Paris were advised to stay home and several Metro lines were closed.

However, queues of people wanting to donate blood in the capital formed, while others have been delivering flowers and messages to the scenes.

Around 1,500 soldiers have been mobilised to protect official buildings, schools and universities.

Disneyland Paris has shut for the day - out of respect rather than security fears, it said - and all sporting events have been cancelled.

Mr Hollande earlier said the country's borders were being shut, but officials later clarified they were just re-imposing border checks which had been removed after Europe created its free-travel zone in the 1980s.

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A "shocked" David Cameron has said Britain must be prepared for a "number of British casualties" .

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