A far-right writer and activist shot himself dead in front of the altar of Paris's famed Notre Dame Cathedral on Tuesday, after calling for "spectacular" action to protect France's identity.
Police confirmed the man's identity as Dominique Venner, 78, an essayist and activist linked with France's far-right and nationalist groups.
His suicide was hailed by Marine Le Pen, leader of the far-right Front National (FN), as a political gesture.
"All respect to Dominique Venner whose final, eminently political act was to try to wake up the people of France," Le Pen said on Twitter, though she added later that "it is in life and hope that France will renew and save itself."
Bruno Gollnisch, an FN stalwart, said Venner's "dramatic act was a protest against the decay of our society."
Police said Venner shot himself with a pistol shortly after 1400 GMT and that the cathedral, which at the time contained about 1,500 people, was then evacuated without incident.
Venner had a long career publishing right-wing essays, military histories and books on weaponry and hunting.
He was a soldier during France's war in Algeria and was a member of the OAS (Secret Armed Organisation), a short-lived paramilitary group that opposed Algeria's independence from France.
In a final essay on his website Tuesday, he railed against France's adoption of a "vile law" legalising gay marriage and adoption, urging activists to take measures to protect "French and European identities".
In a possible reference to his suicide, Venner wrote: "There will certainly need to be new, spectacular, symbolic gestures to shake off the sleepiness... and re-awaken the memories of our origins."
"We are reaching a time when words must be backed up with acts," he added.
The rector of the cathedral, Monsignor Patrick Jacquin, told AFP that Venner had laid a letter on the altar before killing himself. A police source said the letter contained similar writings to those on Venner's website.
"We did not know him, he was not a regular at the cathedral," Jacquin said, adding that he believed it was the first time anyone had committed suicide inside the cathedral.
Greg, an American tourist from Phoenix, said the church was full at the time of the suicide but that there was no panic during the evacuation.
"We just heard a loud sound, like a body falling from above," said Greg, who would not give his last name.
Jacquin said masses had been cancelled and that church officials would hold a vigil later on Tuesday.
"We will pray for this man, as for so many others at their end," he said. "This is terrible, we are thinking of him and his family."
Venner's publisher, Pierre-Guillaume de Roux, said his next book due in June was entitled "A Western Samurai".
He said the writer's death had "an extremely strong symbolic power that approximates (Yukio) Mishima," the radical right-wing Japanese author who committed ritual suicide in 1970.
Gollnisch said Mishima had likely been an inspiration for Venner's suicide.
The Gothic Notre Dame Cathedral on an islet on the River Seine is one of the most visited sites in Paris, attracting 13.6 million visitors in 2011, and is this year celebrating its 850th anniversary.
It was the second dramatic suicide in less than a week in Paris, after a 50-year-old man with a history of family problems shot himself dead Thursday in a primary school near the Eiffel Tower, in front of about a dozen stunned children.