The Pentagon has opened an investigation into an invite-only Facebook group where male marines have been posting thousands of naked or sexually suggestive photos of their fellow female marines—along with a barrage of misogynistic comments, including some saying the women should be raped. Some of the photos were clearly shot without the consent or knowledge of the women, such as a photo of a corporal bent over. Others are private photos or photos taken off social media sites such as Instagram. The invite-only group is called Marines United and includes 30,000 men who are active-duty and veteran soldiers. The Naval Criminal Investigative Service has launched an investigation, and the Marine Corps has warned soldiers they could face court-martial by participating in the group. A 2014 Pentagon report found the Marines has the highest rate of sexual assault of the U.S. armed forces, with an estimated 8 percent of active-duty female marines experiencing sexual assault in 2014 alone.