The French defence ministry lied about the fallout from France's first nuclear test in the Sahara desert in 1960. Radioactivity reached as far as the Spanish and Sicilain coasts to the north and Nigeria and the Central African Republic to the south, declassified documents show.
A map unearthed by the Le Parisien newspaper shows fallout from the test of the Gerboise Bleue bomb in the Algerian desert reaching western Sicily and southern Spain on the 13th day after the test.
In related documents, declassified last year due to a legal case brought by veterans of France's nuclear tests, the military claims that doses were low but expert Bruno Barillot tells Le Parisien that "the norms at the time were a lot less strict than today".
The documents also admit that dangerous levels of iodine-131 and caesium-137 were found in Chad's capital, N'Djamena, as well as Arak, near Tamanrasset in southern Algeria.
"Everybody knows today that these radioactive elements cause cancers or cardio-vascular diseases," Barillot says.
"This means tens of millions of potential victims," lawyer Fatima Benbrahal, who represents Algerians affected by the tests, tells Le Parisien.
Gerboise Bleue (blue jerboa) was the first nuclear bomb tested by France.
It was four times as powerful as the bomb dropped by the US on Hiroshima.
France carried out 210 nuclear tests in Algeria and Polynesia between 1960 and 1996.
Veterans who were present during the tests have suffered cancer and other diseases and have been fighting for compensation for years but only a small number of cases have been accepted as valid.