A mother and her daughter have been arrested for selling body parts from their funeral home for medical research, often without the knowledge of the dead people's families.

Shirley Koch and Megan Hess have been charged with six counts of mail fraud and three counts of illegal transportation of hazardous materials, according to the US Attorney’s Office in the District of Colorado.

Ms Koch and Ms Hess set up the Sunset Mesa funeral home in Montrose, Colorado in 2009.

The attorney's office explained that the two women “were arrested for illegally selling body parts or entire bodies without the consent of the family of the deceased.”

They also offered cremation services for families, but on some occasions never delivered them.

Ms Koch and Ms Hess are accused of committing the crimes from 2010 to 2018.

They are accused of selling body parts and sometimes full bodies to be used for scientific and educational research, not always with the permission of the families.

“In at least dozens of instances, Hess and Koch did not follow family wishes, and neither discussed nor obtained authorization for Donor Services to transfer decedents’ bodies or body parts to third parties,” said the release.

“Hess and Koch also delivered cremains to families with the representation that the cremains were that of the deceased when, frequently, that was not the case. “

US attorney, Jason Dunn commented on the break of trust involved in the crimes, saying that ”this betrays a fundamental trust during one of the worst times in a person’s life -- having to make arrangements for a deceased loved one.”