U.S. Olympic officials have called for the resignations of all directors of USA Gymnastics, the organization that selects and trains Olympic gymnasts. The demand came Wednesday, the same day former USA Gymnastics doctor Larry Nassar was sentenced to up to 175 years in prison for molesting more than 150 women and girls. Among Nassar’s victims were several American gymnasts who won Olympic medals. In an open letter, the head of the U.S. Olympic Committee, or USOC, Scott Blackmun, first apologized to all victims for having suffered as part of the “tragedy” of abuse. He said the USOC was sorry for the “pain caused by this terrible man.” In addition, he admitted that gymnasts “were not provided a safe” environment to seek their sports dreams.