Five men have been arrested on the Swedish island of Gotland for having stolen 1,000 Viking-era silver coins. The entire hoard from which the looters helped themselves to 1,000 coins was over twice that size: 2,000 German, English and Danish coins from the 1060s.

Gotland, a large island in the middle of the Baltic off the southeast coast of Sweden, is replete with Viking hoards. Sadly, it is also replete with looters who illegally dig up whatever treasures they can find, then sell them online or through shady dealers. Since there is so much ground to cover and the weather rarely cooperates to keep looted sites in CSI condition, not only do thieves often get away with it, but the thefts themselves are not discovered.

It was a fortuitous chain of circumstance that brought these scofflaws to justice.

Part of a crucifix from the 11th century was found in the ground where the looters dug. Several days later, an email was discovered by chance with a photo of a part of a crucifix.

A comparison of the find and the image showed that the parts belonged together and that the crucifix came from the hiding place in the field in Gandarve.

“The person who had sent the email was suspected of having attempted to sell the crucifix and he led us on to another person with ties to Gotland,” said prosecutor Mats Wihlborg.

During a raid on a property on Gotland, investigators came across three people with metal detectors, shovels and backpacks. After examining computers and GPS equipment, they also found links between the defendants and two other places where the looters had struck on Gotland.

The looters will be charged with preparation of aggravated crime against relics and aggravated crime against relics. The charges carry a potential sentence of four years in prison. Three of the defendants are thought to be the ringleaders responsible for multiple thefts. The prosecutor is delighted. He noted that it’s extremely rare for cases to actually reach the point of prosecution, and especially not of a full-on looting ring.

Looters are not just hobbyists who stumbled on a treasure and decided to keep it or even sell it on the down low. They are organized, experienced and well-versed in the geography of the island. They often operate at night to avoid detection, and they’re damn good at it. That’s why these arrests are so important to the Gotland authorities.