PARIS (AP) -- Police have detained 19 people in a crackdown on suspected Islamist extremists in cities around France on Friday and more such raids are planned, the French president said.
Nicolas Sarkozy gave no details about the justifications for the arrests, or what specifically the detainees are suspected of.
"It's in connection with a form of Islamist radicalism," Sarkozy said on Europe-1 radio.
A police investigator told The Associated Press that the operation, conducted by the main French intelligence agency, the DCRI, is not connected to an inquiry into a recent spate of killings in southern France. The investigator spoke on condition of anonymity in line with the department's rules.
Mohamed Merah, a 23-year-old Frenchman, claimed responsibility for the attacks that left seven dead. Merah, who espoused radical Islamist views and said he had links to al-Qaida, was killed in a gunfight with police last week and buried near Toulouse on Thursday.
The shootings in Toulouse and nearby Montauban -- when three Jewish schoolchildren, three paratroopers and a rabbi were killed -- were the worst terrorist attacks in France since the 1990s and have revived concerns about homegrown Islamist radicals carrying out violence.
French Muslims have worried about a backlash after Merah's attacks, and French leaders have urged the public not to equate Islam with terrorism.
But concerns about radical Islam are high, and the government on Thursday banned a string of international Muslim clerics from entering France for a conference of a fundamentalist Islamic group.
Sarkozy said he didn't know whether the 19 were part of any network.
"There will be other operations that will continue and that will allow us to expel from our national territory a certain number of people who have no reason to be here," Sarkozy said.
Sarkozy, who is running a tough battle for re-election, added: "It's our duty to guarantee the security of the French people. We have no choice. It's absolutely indispensable."