A letter by Alfred Dreyfus in which the French Jewish army captain wrongly accused of treason over a century ago protests his sentence sold for 380,000 euros ($492,000) at an auction in Paris Wednesday, the AFP news agency reported.
Written to the interior ministry in 1895, a month after he was sentenced for treason in the infamous "Dreyfus affair", the letter had been expected to fetch between 100,000 and 150,000 euros at the Sotheby's auction.
The sale did not have the support of the Dreyfus family, who say the letter should have been donated to a museum or a library instead.
"We urge the seller of this letter to give up this sale," Dreyfus's grandson Charles Dreyfus and historian Vincent Duclert wrote in an open letter.
Dreyfus (1859-1935) -- a Jew from the Alsace region of eastern France, which was occupied by Germany between 1871 and 1918 -- was found guilty in 1894 of passing secret information to the German military attache in Paris and sentenced to life imprisonment at the infamous Devil's Island penal colony.
In 1898 the writer Emile Zola published his famous "J'accuse" letter to the president of the day, naming officials who framed Dreyfus, and the next year the army captain was brought back for a second trial and then officially pardoned -- though not cleared of the charges.
In his prison letter, Dreyfus proclaims his innocence: "I have been sentenced for the most infamous crime a soldier can commit and I am innocent.... I ask you, minister, not for grace or pity, but simply for justice."