Last week, Spanish police arrested a 67-year-old woman accused of stealing a Jean-Michel Basquiat painting in Mallorca, according to a release from the police obtained by artnet News.

The woman allegedly stole the artwork from an unnamed private collector and entrepreneur based in the town of Alcúdia, with the intention of demanding a ransom for its safe return.

According to the local newspaper Diario de Mallorca, both the woman and the collector are British nationals, and the woman had been working for him for some time. The woman, also unnamed by police, claimed she took the piece to push the collector to pay her €30,000 she was owed.

The collector alerted the police last week that the work had gone missing. In a matter of hours, the woman was detained and the painting was located in a house in nearby Pollença. The police brought the work—still in its original crate—back to the station, where the owner collected it. He was accompanied by a team of experts, who certified that the painting had suffered no damage.

Police have not disclosed the estimated worth of the painting, but the release refers to the artwork as “priceless,” given that it was acquired directly from Basquiat’s father and hasn’t been on the market since.

According to the local newspaper, the painting is from 1982, the most coveted year for work by the artist. (Six of the artist’s top 10 auction prices, according to the artnet Price Database, are for works from 1982, including the splashy blue Untitled, which sold for a record-shattering $110.5 million at Sotheby’s in May.)

Some experts, however, have cast doubts on the authenticity of the painting. Diario de Mallorca reports that the editor and art collector Miquel Font believes the work is a fake because of the overuse of certain motifs. “Basquiat used words in his painting, but there are too many here, he didn’t use that many,” he told the local newspaper. The gallerist Frederic Pinya, director of Galeria Pelaires, told the paper that the painting should be authenticated before jumping to conclusions.

The Jean-Michel Basquiat estate’s authentication committee disbanded in 2012, and the estate did not immediately respond to a request for comment on the development.