Is Sarkozy being vigilant? Or political?
Police in France have arrested 19 suspected Islamist militants and seized weapons in a series of dawn raids, President Nicolas Sarkozy says.
The raids were in Toulouse, the home of gunman Mohamed Merah, and other cities.
Merah, who killed seven people in three separate attacks, was buried in Toulouse on Thursday after being killed in a shoot-out with police on 22 March.
Police have been hunting possible accomplices but sources said there was no direct link with the raids.
Mr Sarkozy told Europe 1 radio after Friday's raids: "It's our duty to guarantee the security of the French people. We have no choice. It's absolutely indispensable.
The raids were carried out by the domestic intelligence agency, the DCRI, with the help of the elite Raid police commando group, Agence France-Presse news agency reports.
Several of the raids were in Toulouse, particularly the Mirail quarter, sources told AFP.
But there were also raids in Nantes, which is believed to be a centre for the Forsane Alizza (Knights of Pride) group, to which Merah had been linked by some French media.
It is a Salafist group that was dissolved by the interior ministry in an earlier investigation.
Cracking down on Islamic extremism has been good for Sarkozy's campaign. He is now ahead in the first round election and is narrowing the gap between himself and his socialist opponent for the run off election in May.
Sarkozy has compared the attacks on Jewish children in Toulouse and Montauban to 9/11:
"What must be understood is that the trauma of Montauban and Toulouse is profound for our country, a little - I don't want to compare the horrors - a little like the trauma that followed in the United States and in New York after the September 11, 2001 attacks."
The first vote will take place on April 22.