On Sunday Israeli authorities indicted alleged antiquities robbers who had been caught searching for Dead Sea scrolls in the Judean Desert. The looters were apprehended last week by inspectors from the Israel Antiquities Authority (IAA) and members of the Arad Rescue Unit, marking the first time in 30 years that looters have been caught on the desert cliffs in the Nahal Ze’elim canyon.

According to the IAA, a detailed year-long operation prevented the robbers from making away withhistoric artifacts from “the Cave of Skulls” – a difficult-to-access spot located on the side of the valley’s northern cliff, accessible solely via a narrow goat’s path.

Arad Rescue Unit members were going through routine training when they noticed suspicious activity taking place near the cave. IAA inspectors were brought in to monitor the cave and found the robbers drilling into the earth and damaging the cave, which contains “historic evidence” dating back 5,000 years back to the Chalcolithic period.

Authorities recovered ancient artifacts, including a 2,000-year old lice comb, from the gang.

The six robbers were all young men from the West Bank village of Seir. They were charged for “illegally digging up antiquities,” reports the New York Post.

The artifacts located in the cave have long been a target for looters.

“Over the years, many of the plundered finds reached the antiquities markets in Israel and abroad, but it has been decades since the perpetrators were caught red-handed,” Amir Ganor, director of the Unit for the Prevention of Antiquities Robbery in the IAA said in the release. “This is mainly due to the difficulty in detecting and catching them on the wild desert cliffs.”

According to the IAA, “excavating in antiquities sites without a license and destroying an antiquities site” is a severe violation that can lead up to five years in prison.