Police investigating a suspected neo-Nazi who tried to kill President Jacques Chirac worked to determine if he acted alone. Prosecutors said Monday that the young student was target practicing less than a week before the attack.

Maxime Brunerie, the 25-year-old who pulled a rifle from a guitar case and fired at Chirac during France's pomp-filled national day parade on Sunday, remained interned at a psychiatric facility.

He will stay there at least a month, Paris prosecutor Francois Cordier said. He said psychiatrists have determined that Brunerie, who tried to turn his gun on himself after his shot missed Chirac, is "a menace to himself and others" and cannot be questioned for now.

Brunerie, a student of accounting and management, bought his .22-caliber rifle and two boxes of bullets on July 6, Cordier said. He bought another four boxes three days later, hired a car and went to the Burgundy wine region southeast of Paris to practice shooting, the prosecutor added.

A relative told police Brunerie "was attracted by supremacist movements in North America and the English movement C-18," Cordier said.

Combat 18 is a far-right extremist group that takes its name from the first and eighth letters of the alphabet -- A and H -- the initials of Adolf Hitler.

The shooting renewed debate about crime and the ready availability of guns in France, where hunting is a popular sport and where rifles like the one used are easily bought. Just three months ago, a suicidal 33-year-old unemployed man shot and killed eight officials at a city council meeting in a Paris suburb,

The assassination attempt also provoked renewed warnings about extremism in Europe.

"The far-right background of this abominable deed shows once again how seriously we must take these dangers," said German Chancellor Gerhard Schroeder.

Far-right politicians in several European countries, including French National Front leader Jean-Marie Le Pen, have won votes by playing on fears of immigration and crime. Le Pen stunned France with his strong showing in the first round of presidential elections in April. Chirac crushed Le Pen in the second round, re-elected to a second term with 82 percent of the vote.

The investigation into the attempt on Chirac's life will seek "to determine and verify the conditions that led (Brunerie) to his criminal act," said Cordier, the prosecutor, at a news conference.

He said Brunerie told investigators "that his goal was to put an end to his days and make people talk about him."

Investigators were looking at a computer seized at Brunerie's home south of Paris, Cordier added. He said Brunerie left a message on a British Internet site telling people to watch television Sunday.

The message said "there was going to be a surprise," said a police officer close to the investigation, who spoke on condition of anonymity.

The officer said investigators were trying "to find out if he was alone, if he had accomplices, or if he was pushed into it."

He said Brunerie was known to police, who had him listed on a register of known hooligans. But he said there was no evidence so far to show that Brunerie was helped or encouraged by others.

The newspaper Le Monde said police questioned a couple of extremists Brunerie visited the day before the shooting. Police also were searching for another extremist Brunerie met Friday, the newspaper said.

As investigators focused on Brunerie's far-right contacts, extraordinary details emerged of individual acts of courage by spectators along the parade route who tackled and disarmed the gunman and may have saved the French president's life.

Chirac telephoned four of them Monday, thanking "their intervention, their courage and their sang-froid," the presidential Elysee Palace announced.

Jacques Weber, a tourist from France's Alsace region who got his call from Chirac on Monday morning, said Brunerie looked "really determined" as he took aim. The president, just a couple hundred feet away, was riding an open jeep down the Champs-Elysees, proudly inspecting troops at the Bastille Day military parade.

"I heard a 'clac,' a little click, and I understood he was going to hurt someone. I grasped the gun that was within arm's reach of my left hand and pointed it skywards," Weber told France-Info radio.

"He stuck his chin over the barrel to kill himself and I ripped the gun away," Weber continued. "As two other spectators collared him, I brandished the gun in the air...I shouted, 'Police! Police!' The police came a while later and tackled him. The police thought I was the one who fired!"

Police said Brunerie was linked to a far-right student group, the Groupe Union Defense (GUD), among others. Such extremist groups are small, low-profile, not popular and distinct from the far-right movement led by Le Pen.

But the police officer who spoke to The Associated Press said the GUD and another extremist group, the French and European Nationalist Party, later expelled him because he was "unstable."

French newspapers said Brunerie ran in March 2001 municipal elections for the National Republican Movement, the far-right party of Bruno Megret, who is a former lieutenant of Le Pen.

Megret condemned the assassination attempt, saying in a statement that his party rejects "all forms of extremism."