A security personnel displays a section of 70 adult human skulls and 18 limb bones seized from a restaurant at the India-Nepal border, at Khoribari police station, Aug. 21, 2008. Reuters

Eight men were arrested this week in connection to a human bone smuggling ring in the state of West Bengal, India, after authorities uncovered some 365 bones in a village, CNN reported. The bones were thought to have been pulled from the bodies of deceased people found in the Burdwan district’s rivers, according to the state’s deputy police chief, Ajay Sharma.

“The bones had been cleaned with hydrogen peroxide for sale locally to doctors and medical colleges,” Sharma told CNN.

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West Bengal has been a known hub for black market human trade since a ban on human remains was instated in 1985, according to the Associated Press. Prior to the ban, human rights groups began to question the bone collecting methods. Today, the only legal way in which to obtain human bones in India is through a hospital.

In 2007, authorities uncovered hundreds of human thigh bones and human skulls in India, and arrests were made in connection to smuggling. The smugglers were said to have been taking the remains to Bhutan to be used in Buddhist monasteries.

“During the interrogation they confessed that the hollow human thigh bones were in great demand in monasteries and were used as blow-horns, and the skulls as vessels to drink from at religious ceremonies,” Ravinder Nalwa, and investigating officer, said during the investigation via Reuters.

Buddhist monks in India had said that the mentioned human parts were used by those who practiced a particular Tibetan school of Buddhism.

More recently, human skulls have even been found on the internet. National Geographic published a story in 2016 on human skulls that could be purchased on eBay. Apparently, between 2012 and 2013, scientists had discovered over 450 human skulls listed on the online marketplace.