French police have arrested nine people after a man beheaded a school teacher on the street of a Paris suburb on Friday.
Investigators were trying to establish whether the attacker, who was shot dead by police, had acted alone or had accomplices. French media reported that he was an 18-year-old of Chechen origin.
His victim, a history teacher, had earlier this month shown his pupils controversial cartoons in a civics class on freedom of expression.
Four relatives of the attacker, including a minor, were detained in the immediate hours after the attack in the middle-class suburb of Conflans-Sainte-Honorine, the police sources said.
Five more were detained overnight, among them two parents of pupils at the College du Bois d'Aulne where the teacher was employed.


Kenya tourist helicopter crash kills seven
US, South Korea to cut length, scope of military drills after Trump order
Central African Republic gold mine collapse kills at least 100
Israeli airstrike kills nine Palestinians at Gaza police station
Thai schools hold shooting response drills after deadly school attack
