French police shot dead a suspect during an anti-terrorism raid in the northeastern city of Strasbourg on Saturday that was part of an investigation into a grenade attack last month on a Jewish market, judicial and security sources said.

French officials say DNA on the grenade led them to suspected jihadist cell of young Frenchmen recently converted to Islam.

Police carried out raids across France on Saturday and arrested 10 people, aged between 19 and 25. The man whose DNA was on the grenade, 19-year-old Jeremy Sydney, was killed by police after he opened fire on them, wounding three officers in the eastern city of Strasbourg.

Paris prosecutor Francois Molins said four of the men involved in the raid had written wills.

French President Francois Hollande said in a statement on Saturday that seven people were arrested in the operation. "The president of the Republic confirmed the State's complete determination to protect the French against all forms of terrorist threats," read the statement.

The raids were connected to a September 19 incident in the Paris suburb of Sarcelles in which two men threw a grenade into a Jewish kosher supermarket, wounding one and causing minor damage, security sources said. The attack took place on the same day that a French satirical paper published crude caricatures of the Prophet Muhammad, and while anti-Western protests were growing against an anti-Islam film.

The police unit was fired on after entering a fourth-floor apartment at about 6 A.M. in the Esplanade district of Strasbourg and an officer was wounded by shots that hit his bulletproof vest and helmet.

"During an anti-terrorist police operation in Strasbourg... gunfire was exchanged between police and the suspect. The latter was killed," Strasbourg prosecutor Patrick Poirret said in a statement.

"The group was met with a .357 Magnum [revolver fire]," said Norbert Georgel, secretary for the region's police union, who said the wounded officer's life was not in danger.

Neighbors told Reuters that a couple had lived in the apartment with their two children for the past four to six months. The man was bearded and the woman wore the Muslim full-face veil, they said.

The French Interior Ministry declined comment.

France's Jewish community has been on edge after a series of attacks in recent months. In the worst incident, three Jewish children and a rabbi were among seven people shot dead in March by an al-Qaida-inspired gunman who had attended a combat-training camp in Afghanistan.

France's left-wing government presented legislation this week that would allow police to arrest those believed to have been involved in terrorism-related activity outside French borders.

French President Francois Hollande is caught between trying to appear tough on crime while holding to campaign promises to help underprivileged immigrant communities where poverty and joblessness have bred alienation and, in some cases according to social workers and police, a turn to radicalism.