President Obama called Guatemalan President Alvaro Colom, to apologize to him and the Guatemalan people about new information leaking out about horrific U.S. experiments done to Guatemalans in the 1940s.

According to The Huffington Post, a presidential panel revealed terrible details of the medical experiments, which included re-infecting a dying woman in a syphilis study. Even though the experiments are already a blight on American medical research, panel members have said the new information shows just how unethical the researchers were, even when their actions are placed in the historical context of a different time.

Anita Allen, a member of the Presidential Commission for the Study of Bioethical Issues, said, “The researchers put their own medical advancement first and human decency a far second.”

According to the article, the medical experiments were performed between 1946 to 1948 by the U.S. Public Health Service and the Pan American Sanitary Bureau. The two organizations worked with several Guatemalan government agencies to do research that involved deliberately exposing individuals to STDs–the study was testing whether penicillin could prevent illness in the 1300 people who were exposed to gonorrhea, chancroid, or syphilis. The research was paid for by the American government.

The panel revealed that only around 700 received some level of treatment and that 83 of the infected people died, but it is unclear whether their deaths were directly related to the experiments.

If you want to read more about this, click here to go to The Huffington Post.