French historian kills himself at the altar of Notre Dame Cathedral

A far-right French historian has killed himself at the altar of Notre Dame Cathedral in Paris after declaring that more radical action was needed in opposition to same-sex marriage in France.

Dominique Venner, 78, walked into the building at 4pm and put a letter on the altar before shooting himself through the mouth, according to local media reports. Hundreds of visitors were immediately evacuated from the site, which is the most visited Catholic monument in Paris.

The motive for the suicide and the contents of the letter were not immediately clear, although Marine Le Pen, head of the far-right Front National, tweeted her "respect" for Venner and said his death was an "eminently political" gesture.

Manuel Valls, the French interior minister, arrived as officers cordoned off the site. He told French TV: "At the time of this act, the suicide of a desperate man, there were 1,500 people in the cathedral. These people were evacuated very quickly."

He said worshippers and tourists must have been in shock, adding: "Notre Dame is one of the most beautiful symbols of the capital and our country, and we can measure the impact of such an act."

The rector of Notre Dame, Monsignor Patrick Jacquin, said it was the first suicide in decades at the 850-year-old cathedral, which is visited by some 13 million people each year, and perhaps the first time anyone had taken their own life in the building. "It's unfortunate, it's dramatic and it's shocking," he said.

Venner, a historian and former member of the Secret Army Organisation that opposed Algerian independence in the early 1960s and waged a terror campaign against Charles de Gaulle's government, had written on his blog on Tuesday about his anger over the recent legalisation of same-sex marriage, which he called vile.

Referring to a rally planned for Sunday against the law, which also amended adoption rights, he said the demonstrators were "right to shout their impatience and anger".

He also wrote of what he described as the risk of "a France fallen to the power of Islamists", saying that for 40 years all governments and parties, except the Front National, businesses and the church had accelerated north African immigration. He added that there needed to be "new gestures, spectacular and symbolic" to "reawaken the memory of our origins". He added: "We're entering a time where words should be authenticated by actions."

The bill became law on Saturday after a parliament vote and months of street protests, political slanging matches and a rise in homophobic attacks.