According to CNN.com, the United Nations is currently investigating claims against terror group, ISIS, regarding organ theft. ISIS — noted as the wealthiest terror group in recorded history — is reportedly selling organs stolen from slain civilians.

The topic was made known by an Iraqi ambassador Feb. 17, though no hard evidence has been revealed to support the organ trafficking claim.

The ambassador, Mohamed Alhakim, urged an investigation to look into the deaths of 10 male doctors and two female doctors in Iraq. Alhakim claimed the 12 were executed after refusing to take part in organ harvesting. According to Alhakim, the bodies were found in shallow graves during the last couple weeks, mutilated and/or bearing surgical incisions.

Alhakim claims there’s a European market for stolen organs and that air travel is utilized to transport the body parts.

 “At this point we’re not in a position to corroborate what he [Alhakim] says, but obviously any source of illegal financing of groups such as ISIS or other extremist groups is extremely worrisome,” said U.N. spokesman Stéphane Dujarric in an interview with CNN.

The U.N. special envoy handling Iraq, Nickolay Mladenov, told CNN that rumors that the group “is using human trafficking as part of its sources of income” have been in circulation the past couple months.

The U.S. Treasury claims ISIS takes in about $1 million a day, pulling their funds from a variety of means, including black market oil sales, robbing banks and gold shops, social media and various means of extortion.

This claim is but one of the barbaric doings ISIS allegedly takes part in, which include mass beheadings, crucifying children, throwing people from building tops and burning people alive.