Paris, Nov. 15 (The Telegraph): The Paris attacks were carried out with the help of three French brothers with Belgium ties, said officials who asked for the public's help in finding one of them.

The French authorities said they were seeking Abdeslam Salah, 26, and described him as dangerous. The police warned the public: "Do not intervene on your own, under any circumstances."

Late tonight, France said it had launched its biggest air strikes in Syria to date, targeting the Islamic State's stronghold in Raqqa.

Belgian officials said that one of Abdeslam's brothers, Ibrahim, had died in the Paris massacre, which killed at least 132 people. Another brother, Mohamed, was detained yesterday in the Molenbeek area of Brussels in Belgium.

A Reuters report said: "Two of the attackers who brought carnage to Paris were French nationals living in neighbouring Belgium, officials said on Sunday. One of them blew himself up in the assault, while the other was arrested on Saturday as he tried to cross the border."

It was not clear whether the arrested person mentioned in the Reuters report is Abdeslam's brother Mohamed, nor whether the arrested person had any direct role in the attacks. Reuters said one of seven people arrested in Belgium on Saturday was believed to have spent the previous evening in Paris.

French officials had initially described eight attackers, but on Saturday night said that only seven of them had died - six by blowing themselves up and one in a shootout with police. A hunt is on for an eighth man, intelligence sources said, and hours later, Abdeslam's name and photo were released.

Salah, the wanted suspect
One dead attacker has been identified as Ismael Omar Mostefai, a 29-year-old who lived in the city of Chartres, southwest of Paris. Mostefai, along with two other gunmen, killed 89 people at the Bataclan concert hall.

Mostefai was identified through tests on his severed finger. Officials said he had a security file for radicalisation.

Mostefai was the middle of five children born to an Algerian father and a Portuguese mother, and he once worked at a bakery, according to a former neighbour.

"It was a normal family, just like everybody else," said the neighbour, who spoke on the condition of anonymity. "He played with my children. He never spoke about religion. He had a joie de vivre. He laughed a lot."

"It was in 2010, that's when he started to become radicalised," the neighbour said. "We don't understand what happened."

The holder of a Syrian passport found near the body of one of the gunmen who died in Paris was registered as a refugee in several European countries last month, authorities said.

Greece identified the man as 25-year-old Ahmad al-Mohammad, from the Syrian city of Idlib, and said he had entered Europe through the Greek island of Leros, where he was processed on October 3.

France has not yet publicly said so but a Greek minister said French officials suspected that Ahmad was one of the attackers. Any confirmation could change the tone of the debate on refugees. (See Page 3)

Belgian officials said the seven people were arrested after two Belgian-registered rented cars were discovered in Paris, both suspected of having been used by the attackers.

One of them, a grey Volkswagen Polo, was abandoned near the Bataclan after being used by the three terrorists who died there. The other, a black Seat Leon, was found on Sunday morning in the eastern Paris suburb of Montreuil. Three Kalashnikov rifles were found inside it.

Three of the seven arrested in Belgium had passed through a roadside check in Cambrai, France, at 9.10am on Saturday. They made their way to Molenbeek where they were detained. The car was seized.

Molenbeek, a poor, immigrant quarter of the Belgian capital, has already been viewed as a possible launch pad for violence. Analysts have long seen Belgium, with its population mix, fragmented state structures resulting from divisions between French and Dutch speakers, and a history as a firearms market as a breeding ground for violent extremism.

Per capita, Belgium has contributed the highest number of foreign fighters to the war in Syria among European countries - more than 300 by official estimates a year ago.

Belgium's central position in Europe and its small size favour the movement of people "with hostile intent". Across borders normally unchecked, Paris lies barely three hours by road and less than 90 minutes by high-speed train from Brussels.

New York Times News Service and Reuters

Photo credit: The Telegraph