That these works are sometimes fake or misleadingly labeled is no surprise to art experts and to foundations that monitor online art sales. But fraud has saturated certain sectors of the art market, experts say. 

“In every country that I visit, even Abu Dhabi, I’m approached by artists or estates who are desperate about the fake situation,” said Véronique Wiesinger, the director and senior curator of the Alberto and Annette Giacometti Foundation in Paris. “We counted the other day 2,005 fake Giacometti sculptures for sale” on just one Web site, she added. 

Many reputable online sellers, of course, deliver precisely what they advertise. “There is a lot of buying online, and most people are satisfied,” said Alan Bamberger, an art consultant and appraiser. 

Over the last few years the Internet has broadened the art market far beyond the exclusivity and opaque jargon of its moneyed enclaves and has helped turn the slogan “art for everyone” into reality. But it has also become a sort of bazaar, where shoppers of varying sophistication routinely encounter all degrees of flimflammery, from the schemes of experienced grifters to the innocent mistakes of the unwitting and naïve. A recent study by statisticians at George Washington University and the University of California, Irvine, estimated that as many as 91 percent of the drawings and small sculptures sold online through eBay as the work of the artist Henry Moore were fake.

Just a few hours later, however, the operation fell apart when Mr. Dogaru received a warning that the police were tapping his cellphone. Today, six months on, the fate of the paintings is still unknown, as law enforcement authorities in Romania and the Netherlands, as well as art lovers around the world, struggle to penetrate the fog of claims and counterclaims about what happened to the masterpieces, from the Kunsthal museum in Rotterdam.

Have they been burned, as Mr. Dogaru's mother, Olga, has at times claimed? Or perhaps spirited away by a tall mystery man in a fancy black car, as she has asserted at other times? Or could they, as many in the desolate village of Carcaliu believe, simply be hidden somewhere in this rural corner of Romania?

Mr. Dogaru appears to have hidden the works initially in his family home but later moved at least some of them in a suitcase to the house of his mother’s sister, Marfa Marcu. Mrs. Marcu, in an interview, said she had never opened the suitcase. She says she last saw it when her sister took it away, along with a shovel, soon after Mr. Dogaru’s arrest. 

Mrs. Dogaru has told prosecutors that, with the help of her son’s girlfriend, she buried the case in the yard of an abandoned house. After a few days, they dug it up, wrapped the paintings in plastic and buried them in a nearby cemetery. 

The trail then goes cold. In an interview with prosecutors on Feb. 27, Mrs. Dogaru said that sometime in January, this time acting alone, she dug up the paintings and, desperate to destroy the evidence of her son’s theft, brought them home and burned them all — in a stove used to heat water for the bathroom and a sauna. 

How she managed to do this is not clear. The stove in which Mrs. Dogaru claimed to have shoved all the artworks is barely a foot wide and seems far too small to contain what would have been a bulky bundle of canvas and wood. 

In a written statement on Feb. 28, Mrs. Dogaru retracted the incineration story and said she had, in fact, handed the paintings to a Russian-speaking man, about 40, who arrived at her house in a black car. She explained that her son, whom she visited in prison to get instructions, had told her to expect such a visitor and to give him the paintings.

If international legal authorities and American civil courts agree, the law could establish 1925, rather than 1993, as the dividing point after which Cambodian artifacts taken without government permits can be treated as stolen property. Cambodia would still have to prove that the statue was looted after 1925, “a high burden but not an impossible one,” according to Mr. Bogdanos, who agrees the 1925 law “appears to be valid.”