Ghent, Belgium ? Even though the painting has not been seen since 1934, it is becoming more popular by the day.

It is almost 70 years since the disappearance of a panel scarred one of Western art’s defining works. Now, the theft of Jan Van Eyck’s “Just Judges” is taking on ever more mythic proportions.

The mystery only increased after a much publicized hunt for the highlight of Flemish primitive painting ended in disappointment last month when a secret cache in a church in northern Belgium turned out to be empty.

“It is our monster of Loch Ness,” said author Patrick Bernauw, who has written a book on the audacious theft. “When it wasn’t found last month, the myth just reinforced itself a little bit more.”

The search captured front pages throughout Belgium and beyond and the probe in the church was carried live on radio. Television broadcasts opened their news on location and a Web site set up to highlight the discovery crashed under the weight of 75,000 hits a day.

For decades, a determined bunch of die-hard amateur detectives has picked up where police left off many years ago. For many, the concept is just too enticing: It unites a stupendous piece of art and a great detective story.

The 20-panel “Adoration of the Mystic Lamb,” completed in 1432, offers a translucent use of color created by layer upon layer of oil and intricate detail and mystical meaning which set an example for generations of artists. The “Just Judges” panel depicts 10 men on horseback on their way to venerate the Holy Lamb. It highlights what made Van Eyck famous ” beautiful light, intricate details and composition.

The panel was stolen along with a lesser panel on April 10, 1934, from the Saint Bavo Cathedral. Soon after, extortion letters sent to the bishop of Ghent demanded $25,000.