PARIS/ALENCON, France (Reuters) - The voice that claimed Islamic State was responsible for the deadly Paris attacks is known to many in the small French provincial town of Alencon.
To family, Fabien Clain was a "big teddy bear", to neighbors he was polite and at the local mosque he was a fellow worshipper who came to pray.
To the French authorities, he was a veteran jihadi jailed once in the past for recruiting militant fighters and believed by them to have fled to Syria this year. They now think he may have played a bigger role in the Nov. 13 attacks, the worst in France since World War Two.
In the online audio message detailing the assaults and claiming they were orchestrated by Islamic State, Clain’s voice sounds haunting and triumphant. He warns the massacre "is only the beginning of the storm".
Investigators are now looking at what Clain's role might be and how it fits with that of Belgian Abdelhamid Abaaoud, whom they believe to be a ringleader. Police are now asking whether Clain may have been more important.
"There is no definitive scenario, everything is being looked at," a source close to the investigation said. A police source added: "It's possible. I wouldn't be surprised."
A judicial source familiar with anti-terror cases went further: "When you make a claim like that (for the attacks), you're in the operational ranks," the source said.
Police are also looking into Clain's younger brother Jean-Michel, who authorities say sings on the five-minute recording.
Investigators are unsure whether the two brothers are now in Europe or Syria.
Originating from the French territory of La Reunion, the 37- and 35-year-old siblings have previously been linked to radical cells in France and Belgium, according to judicial sources.
Their names have appeared in investigations into planned attacks, like one foiled on churches in a Paris suburb this year and a previous suspected plot on the Bataclan music hall, one of the bloodiest scenes in the Nov. 13 carnage.
It is the elder Clain, who goes by the name Omar, who is the main focus for French authorities. Only six years ago, he was jailed for recruiting jihadis to fight in Iraq.
Clain converted to Islam in the late 1990s. Like his younger brother, he is believed by French police to have become radicalised in the early 2000s when he lived in the southern city of Toulouse where he frequented radical networks and played a role in the militant recruitment "Artigat cell". Members of that cell were believed to have been mentored by Salafist preacher Olivier Corel, known locally as the "white emir".
A French national of Syrian origin, Corel, who lives in the Pyrenees village of Artigat, is also believed by French police and intelligence to have mentored gunman Mohamed Merah, who killed seven people in March 2012.
"It is possible (that the brothers ranked above Abaaoud for the Nov. 13 attacks) because they have been involved in radical movements for a long time," a police source said. "Abaaoud was still young when they were already part of the Artigat cell."
As part of a security operation targeting Islamists under the state of emergency imposed in France after the attacks, police raided Corel's house this week, handing him a suspended jail sentence for possessing a hunting rifle. He is not believed to have any link to the Paris attacks.
Born on Jan. 30, 1978 on France's Indian Ocean island La Reunion, Fabien Clain moved as a child to Alencon in southern Normandy where he grew up with his brother and two sisters.
He returned to La Reunion as a teenager before eventually coming back to Alencon, where he married a school friend, Mylene. The brothers converted their family to Islam and when they moved to Toulouse, their wives wore the niqab veil over their faces, an unusual sight in the city back then.
On Copains d'avant, a French social web site similar to Friends Reunited, Clain's profile lists him as living in "Toulouse, Egypt". Judicial sources say both brothers studied Arabic in the north African country in the mid 2000s.
It is unclear when the page was last updated. It also features class photos, lists history and basketball as hobbies and the words "Still here, thanks be to God".
Clain also lived in Belgium, where French President Francois Hollande has said the Nov. 13 attacks were organized, for about a year in 2004, according to a judicial source.
Back then, the older brother was already suspected of being part of a group of radicals from France living in Belgium, the source said.
Authorities began investigating the Artigat cell some 10 years ago when Syrian police arrested two Frenchmen trying to cross the border into Iraq as part of an Al Qaeda cell.
One member of the cell, Sabri Essid, who is Merah's half brother, took part in "physical training sessions" with Clain, according to other members questioned by police, another judicial source said.
Both he and Clain were sentenced to five years in jail in 2009. Jean-Michel was questioned for four days but released with no charges.
Also in 2009, French authorities opened an investigation into a plot to attack the Bataclan, where the bloodiest of the Nov. 13, 2015 attacks took place. There was not enough evidence and the investigation was eventually dropped in September 2012.
But the Clain brothers' name came up when the main suspect, a Belgian man of Tunisian origin, told police he was "very close" to them and that they had introduced him to a jihadi forum known for using techniques to avoid detection.
Another witness in the Artigat investigation told police Clain had "a true talent for converting people", according to judicial sources.
Clain spent three years in jail. He was behind bars when Merah carried out his killing spree in March 2012. Judicial and police sources believe the two had strong ties.
Samia Maktouf, a lawyer for one of the Merah victim's families, said she had asked prosecutors to question men linked to the Artigat cell, including Clain, but her request was not heeded.
"Everyone thought this was a sleeping cell," she said.
Yet in September 2012, police opened an investigation into Artigat members fleeing to Syria. It is still under way today.
Essid reappeared in an Islamic State video this year in which a child shot dead a man.
Banned in 22 French districts after his release from jail, Clain returned to Alencon with his wife and children in 2012.
At a small apartment complex on the town's outskirts, a buzzer on the three-storey building still bears his name. Inside, his letter box is full.
Last week, police raided the Alencon flat of his cousin and limited her movements, telling her to regularly check in.
"When I heard the audio, I was so shocked," the cousin, who spoke on condition her name not be used, told Reuters. "I just don't understand. I don't know him any more."
Repeatedly saying she had no links to the attacks, the cousin said she had last seen Clain "at the start of the year". Neighbors and worshippers at Alencon's Mahabba mosque, which he attended from late 2012 to early 2015, said they had seen him in February.
"I saw his wife in May/June when a family member died. After that I didn't see her," the cousin said.
"I was in touch once for the children and when she told me she was there (in Syria) ... She said they were well."
Mylene's mother last saw her daughter in February in Alencon. According to a neighbor, police had seized Mylene's passport and those of her children but she still managed to evade French authorities. When her mother eventually noted her disappearance, she alerted police, but it was too late.
"She is devastated," the neighbor said.
Prosecutors opened a preliminary investigation in March into Clain's disappearance and presumed flight to Syria. This was turned into an official judicial probe in June.
Jean-Michel is also believed to be in Syria with his wife and children, a police source said, adding there were questions whether he was even still alive, meaning he could have recorded his singing beforehand.
Before he disappeared, Clain sold halal goods such as soap and massage oils in Islamic shops, according to his cousin.
Standing in her doorway and often in tears, she said she rarely saw Clain and that she spent more time with his wife and children, often going shopping together or watching television.
Their family life was "extremely centered on religion".
"He was so kind, he wouldn't even hurt a fly. He was like a big teddy bear ... always smiling, laughing, joking around," she said. Now she says she has cut off contact.
Other neighbors of Clain paint the picture of a robust but quiet neighbor, seen as often in a robe as in casual clothes.
At the local Mahabba mosque, Clain taught Arabic to young children for about two weeks, until a 2013 television report linked him to Merah airing their photos.
"When that picture aired, people began distancing themselves," Omar Sadequi, head of the Mahabba mosque association, said.
"But you can't stop people coming to the mosque."
Sadequi, who said he had very little contact with Clain, added the mosque banned groupings on its territory.
At a lunchtime worship this week, the few worshippers there recalled seeing Clain, but added they did not really talk to him.
"He had given people the impression that he had changed (after prison)," Sadequi said. "But really, he did not change at all."
Chine Labbe reported for this article from Paris, Additional reporting by Gérard Bon in Paris and Julie Rimbert in Toulouse, Writing by Marie-Louise Gumuchian, Editing by Andrew Callus and Timothy Heritage