PARIS -- Traces of DNA on an orange juice bottle and a surveillance video of a man praying in a mall led to the arrest Wednesday of a young suspect accused of stabbing a French soldier who was patrolling a crowded area just outside Paris, officials said.
The attack came days after a British soldier was slain on a London street in broad daylight, raising fears of potential copycat strikes. France has also been on heightened security alert since its military intervention in January in the African nation of Mali to oust Islamic radicals.
The French soldier is recovering from his injuries and has been released from the hospital.
The suspect was captured on camera offering a Muslim prayer in a corner of a busy shopping mall 10 minutes before he went after the soldier Saturday at the La Defense financial and shopping district, French prosecutor Francois Molins said Wednesday at a news conference in Paris.
The 22-year-old French suspect, identified only by his first name Alexandre, bought the juice and the pocketknife used in the attack an hour beforehand, Molins said.
"The intent to kill is obvious. The suspect doesn't hesitate to stab several times with impressive determination," Molins said.
The suspect was arrested Wednesday outside Paris at the house of a friend who has not been implicated.
"The suspect implicitly confessed when he told police `I know why you're here,"' Molins told reporters. "The nature of the attack, the fact that it happened three days after the London attack and a prayer that was carried shortly before the attack make us believe that he acted in the name of his religious ideology and that his wish was to attack someone representing the state. "
The suspect, who was unemployed and homeless, was identified through DNA on a plastic juice bottle, said Christophe Crepin, spokesman for the police union UNSA.
Molins said the man came under scrutiny after a street prayer in 2007 and authorities had his DNA profile on record after a series of petty crimes as a minor. He converted to radical Islam around age 18, Molins said.
Under French anti-terrorism law, he can be held for 96 hours without charge.
Police will be investigating the suspect's Internet searches, his travels and contacts to determine whether Alexandre acted alone or was part of a network, said Louis Caprioli, France's former top anti-terrorism official.
"The early indications seem to suggest he acted alone," said Caprioli, now a security consultant at French risk management group GEOS. This would be the first time a French Muslim convert committed a lone-wolf style terrorist act, rather than as part of a terrorist network, Caprioli said.
Lone wolf attacks are the most alarming, Caprioli said, "because it's completely unpredictable."
French security forces have been on heightened alert since the military intervened in the African nation of Mali in January to regain territory seized by Islamic radicals. Yet even before the French military action in Mali, French soldiers were considered possible targets at home by local radicals.
Last year, three French paratroopers were killed by a man police described as a French-born Islamic extremist. Mohamed Merah went on to attack a Jewish school in southern France, killing a rabbi and three Jewish children in March 2012 before being killed later that month in a gunbattle with police.
"I have said before: There are dozens, if not hundreds of potential Merahs in our country," Interior Minister Manuel Valls told the iTele network.