PARIS: Just a few weeks ago, Mohammed Merah partied at a nightclub, and an acquaintance noticed nothing out of the ordinary. Another friend said the former car body shop worker liked to talk about 'cars, bikes, girls and sports'.
But for European law enforcement officials, he represents the kind of insidious terror threat that they fear most: a home- grown militant, consumed by visceral grievances, who identifies with Al-Qaeda but operates on his own.
'He appears to be part of the new generation of Islamic terrorists who act alone, abetted by jihadi websites and their own anger,' said Mr Jean-Louis Bruguiere, a former French counterterrorism judge and expert on European terrorism.
As a stunned nation grappled with its deadliest terrorist attack since 1995, a portrait has emerged of a disturbed and volatile man who was known to domestic intelligence, having been put on a watch list several years ago.
He operated on the fringes of French society, a soft-spoken and alienated youth who railed about the plight of the Palestinians and engaged in petty crimes such as purse-snatching.
It was during one of his stints in prison that Merah, a French citizen of Algerian descent, became politicised. He later travelled to Afghanistan and Pakistan, where he said he received training. French Interior Minister Claude Gueant said that Merah told the police on Wednesday that he called himself one of the 'mujahideen' and claimed to be a member of al-Qaeda.
There has been concern all over Western Europe about young, second-generation Muslims like Merah, particularly those from Pakistan, North Africa or Turkey, who become radicalised through the Internet or periods in jail, and then travel to Afghanistan, Pakistan, Yemen or other hotbeds of radical Islam before returning home.
Much of the concern about domestic terrorism in Britain, Belgium, Germany and France has focused on these young people, who may have had little formal religious education but are susceptible to calls for jihad, especially when their own lives have been marked by disappointment, crime, racism and joblessness.
But nothing about Merah's social life in Toulouse before the attack made him stand out as a radical bent on sowing terror - or indicated that he even had radical leanings, according to an acquaintance. Mr Mehdi Nedder, 31, described Merah as a 'normal young man'.
'Three weeks ago, he was at a nightclub,' Mr Nedder said. 'And this morning, I hear we're talking about Al-Qaeda. How can you change like that in three weeks?'
Another of Merah's friends, who would identify himself only by his first name, Kamel, recalled playing football with him as the two grew up in Toulouse.
'(He) was respectful and generous,' said Mr Kamel, 24. 'We never spoke about weapons, religion or politics, but cars, bikes, girls and sports.'
Merah was a mechanic who was rejected by the army twice, according to news reports. He was known by the police for committing crimes on a regular basis, and had nearly a dozen convictions on his record, said the Interior Ministry.
He had recently been sentenced to a month in jail for driving without a licence.
For Mr Dominique Thomas, a specialist on radical Islam, Merah 'seemed to be a delinquent who was poorly integrated in society and failed at school. What came out is a feeling of hatred and a desire for revenge. He didn't seem to have a structured jihadist ideology but channelled his hatred and claimed an Al-Qaeda affiliation'.
THE NEW YORK TIMES, ASSOCIATED PRESS, AGENCE FRANCE PRESSE