(CNN)Said and Cherif Kouachi, who are the leading suspects in Wednesday's attack on the magazine Charlie Hebdo in Paris, grew up in a world of poor job prospects, life in the French equivalent of the projects and prison time that is not untypical for the French "underclass," which is disproportionately Muslim. On Friday, the two brothers were killed in a shootout with police, achieving their goal of a supposedly heroic "martyrdom." Before they died, one of the brothers spoke on the phone to a journalist from the French news network BFM saying, "We are just telling you that we are the defenders of Prophet Mohammed. I was sent, me, Cherif Kouachi, by al Qaeda in Yemen. I went there and Sheikh Anwar Al-Awlaki financed my trip... before he was killed."
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Peter Bergen: As with some other French Muslims, the brothers were marginal, economically and socially
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He says they became active in Middle East causes, had contact with other prisoners
He fell under the spell of a militant cleric in the 19th arrondissement, a gritty immigrant-dominated suburb of northeastern @placeholder that has little in common with the glamorous French capital city that is known to tourists.