Forensic specialists examining ash found in the stove of a Bulgarian woman to see if it is the remains of seven paintings by Picasso, Matisse, Monet and others that were stolen last year from the Netherlands, have found traces of canvas, paint and nails.
The finding is evidence that Olga Dogaru might have been telling the truth when she claimed to have burned the paintings, which were taken from a Dutch museum last year in a daring daylight heist.
The theft of seven masterpieces, with an estimated value of between £86m-£172m, from Kunsthal Museum in the Netherlands sparked an international hunt and prompted a listing on the Interpol register of stolen art - which would have made sale of the art works virtually impossible on the open market.
Prosecutors have now said that Romania's National History Museum is examining ashes found in the stove of Olga Dogaru, mother of Radu Dogaru, one of three Romanian suspects charged with stealing the paintings from Rotterdam's Kunsthal gallery in a daytime heist.
The robbery, which was the biggest art theft in over a decade in the Netherlands, took place despite hi-tech security measures at the museum.
Police took just five minutes to respond to alarms at the building but by the time they arrived the thieves had already made off with a Picasso, two Monets, and a Matisse, among others.
According to court documents Olga Dogaru admitted last week to torching the artwork to "destroy evidence" after her son's arrest.
Ernest Oberlander-Tarnoveanu, director of Romania's National History Museum, said museum forensic specialists found "small fragments of painting primer, the remains of canvas, the remains of paint" and copper and steel nails, some of which pre-dated the 20th century.
"We discovered a series of substances which are specific to paintings and pictures," he said, including lead, zinc and azurite.
He refused to say definitively that the ashes were those of the seven paintings stolen from Rotterdam's Kunsthal gallery last year, because he said it was not his position to do so. He said justice officials would make that decision.
He did venture that if the remains were those of the paintings, it was "a crime against humanity to destroy universal art".
"I can't believe in 2013 that we come across such acts," he said.
Mr Oberlander-Tarnoveanu said forensic specialists at the museum have been analysing ashes from Ms Dogaru's stove since March and will hand their results to prosecutors next week.
Three Romanian suspects were arrested in January, but the paintings have not been found.
Additional reporting by Associated Press
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