Mohammed Merah, a French national of Algerian descent, grew up in a tough part of Toulouse, raised by a single mother along with two brothers and two sisters.
Amid numerous arrests, mostly for petty crimes such as purse-snatching, his mother and older sister despaired of keeping him on the right track. He had 18 convictions on misdemeanours and in 2007 and 2009 spent two brief spells in prison, France's Le Point magazine reported, where he apparently fell in with radical Islamists. He sometimes wore a beard, and sometimes shaved it off. Sometimes he seemed devout to friends; at other times he'd go clubbing, staying out to listen to raï, popular Arab music.
Paris prosecutor François Molins told a news conference Mr. Merah, 23, had been to the Afghanistan-Pakistan region twice and to the Pakistani militant stronghold of Waziristan for training. He has been on the radar of French domestic intelligence services since returning home.
Mr. Merah is said to be a mechanic by trade but is reported to have been unemployed for several months. Neighbours described him as quiet and helpful, but some worried about signs of his radicalization when they saw him praying in a soccer field close to his home. Christian Ételin, a lawyer who has represented Mr. Merah in the past, described him as "polite" but "complex."
Two of Mr. Merah's friends said he was a "nice guy" who "got on well with everyone," French newspaper JDD reported.
One of them, Samir, said Mr. Merah had been seen in a Toulouse night club only last week, around the time he is believed to have shot and killed three French soldiers. "I served in the army," Samir added, "and he never said anything to me about it."
An unnamed young man who ran into Mr. Merah at a raï nightclub around the time of the first shooting painted a different picture for the French magazine, Le Nouvel Observateur.
"He's a waster, a layabout," he said. "A loner. Not a serious guy. … Sometimes he had his hair long, sometimes short, sometimes red."
Mr. Merah's 29-year-old brother, Abdelkader, who worked in construction, had been implicated in a 2007 network that sent militant fighters to Iraq, but was never charged, Mr. Molins said.
Interior Minister Claude Guéant said officials brought Mr. Merah's mother to Wednesday's standoff but she would not intervene. "She was asked to make contact with her son, to reason with him, but she did not want to, saying she had little influence on him," Mr. Guéant said.