Yesterday, The Center for Investigative Reporting published a report that revealed that the Naval Criminal Investigative Service (NCIS) has launched an investigation into hundreds of Marines following the discovery of a secret Facebook group that was used to spread naked pictures of service women.

The report, authored by Thomas Brennan, founder of a nonprofit news organization called The War Horse, revealed that pictures of the service women were shared on a private Facebook group called Marines United, either posted to the site itself, or via links to a Google Drive folder. The group consists of nearly 30,000 members, some of whom posted comments on the images.

The group was originally founded in 2015, and open to male members of the US Marine Corps, Navy Corpsmen, and the British Royal Marines. According to a description from a retired Marine on Reddit, the group has a history with this type of content, with a “vast majority of the posted items were pictures of girls posts without permission, revenge porn, creepy stalker-like photos taken of girls in public, talk about rape, racist comments and just straight bullshit.”

Posts attracted thousands of comments, urging users to post additional photographs

Brennan’s report outlined that the images or links posted to the group, attracted over 2,500 comments, some of which urged users to upload additional images. In some cases, the explicit images were also accompanied by information on their subjects, identifying more than two dozen female service members by their names, ranks, duty stations, and branches. While some images were reportedly taken illicitly, others appeared to have been stolen from private accounts.

In January, the Marine Corps assigned its first female Marines to Infantry roles, over a year after former Defense Secretary Ash Carter announced that combat jobs would be open to female service members across the armed forces. According to Brennan, the pictures began circulating a month after the placement of those service women, and that the military launched an investigation upon being contacted for comment. The investigation is “in support of two individuals affected by postings on the Marines United site,” while legal and other resources will be provided to assist other affected individuals.

Brennan reports that at least one Marine who shot illicit photographs has been discharged from Active Duty, while “hundreds of Marines” are currently being investigated. A veteran who was responsible for first posting a link to the photos on Google Drive was fired from his position as a government contractor. Some of the social media accounts and Google Drive folders responsible for sharing the images have been deleted. Google declined to comment on the issue.

Following the publication of the report, Brennan, a Marine Corps veteran, and his family have received threats. “There's a "bounty on pictures of my daughter,” Brennan told the Marine Corps Times. “It has been suggested that my wife should be raped as a result of this, and people are openly suggesting I should be killed. ... Can you imagine being one of the victims?"

“The Marine Corps is deeply concerned about allegations regarding the derogatory online comments and sharing of salacious photographs in a closed website.”

Reached by email, Captain Ryan E. Alvis of the Office of Marine Corps Communications told The Verge that she would not comment directly on the investigation, but noted that "the Marine Corps is deeply concerned about allegations regarding the derogatory online comments and sharing of salacious photographs in a closed website. This behavior destroys morale, erodes trust, and degrades the individual,” and that the Marine Corps is taking the allegations seriously. She pointed to Article 133 (for officers) or Article 134 of the Uniform Code of Military Justice, which specifically prohibits the sharing of images without a user’s consent, and that violations might be met with criminal investigation or administrative action.

General Robert Neller, the Commandant of the Marine Corps issued a statement:

I am not going to comment specifically about an on-going investigation, but I will say this: For anyone to target one of our Marines, online or otherwise, in an inappropriate manner, is distasteful and shows an absence of respect. The success of every Marine, every team, every unit and command throughout our Corps is based on mutual trust and respect. I expect every Marine to demonstrate the highest integrity and loyalty to fellow Marines at all times, on duty, off-duty, and online. I expect Marines to give their all to be the best human beings, teammates, and Marines possible.

Requests for comment from Facebook and Google were not returned before publication. We’ll update this post if we hear back.

The United States Armed Forces have been forced to contend with sexism in its ranks and in its service academies as women are integrated into combat positions. One female Marine, who spoke to The Verge on the condition of anonymity, noted that while she did not believe that she was directly impacted by this specific incident, she had been personally affected “by this type of thing.”

Update March 6th, 7:53AM ET: Updated to add word from the Marine Corps Times.

Updated to add comment from Google.