Updated at 14:17 on May 30, 2005, EST.

Specialists cast doubt on authenticity of $650,000 Chagall painting

MINSK, Belarus (AP) - Specialists cast doubt Monday on the authenticity of a painting said to be by late Belarus artist Marc Chagall, which sold at auction Sunday for $650,000 US.

A Belarusian citizen made the winning bid for the oil-on-wood painting of a rooster Sunday after an expert he brought with him judged it to be a genuine Chagall, said Lyudmila Kononova, executive director of the Paragis antique and auction house.

But Tamara Karandasheva, head researcher at the Belarus National Art Museum's Western European art department, said the way the work was painted "leaves no doubt that it is a fake."

The chief curator at Moscow's Tretyakov Gallery, where a major Chagall exhibition ended Sunday, also expressed doubt, saying that an expert who was shown a photograph of what appeared to be the same painting believed it was not a real Chagall.

The curator, Yekaterina Seleznyova, also said that a painting that appeared to be the same one had been examined three times by the Marc Chagall Committee in Paris, which each time said it was not found to be authentic.

Kononova said the painting's "special charm" is that it was executed on a slab of wood meant for an Orthodox Christian icon. She said Chagall painted it between 1910 and 1920 and gave it to an acquaintance. It had been in a private collection.

Karandasheva, however, said that Chagall - who was born in 1887 near the town of Vitebsk in what is now Belarus - did not begin painting roosters until 1926, in Paris.

Chagall died in France in 1985.