For years, the chief of the Border Patrol was a member of the secret CBP Facebook group for racist and threatening chatter

Last week, Propublica revealed the existence of "I'm 10-15", a secret Facebook group for current and former Customs and Border Protection employees -- a group with 9,500 members, while CBP's total workforce numbers 58,000 -- where it was commons for members to share violent, racist, sexist, misogynist, rape-y memes, including some that threatened and disparaged members of Congress.

At the time, CBP officials acted surprised to learn of the group's existence and vowed to investigate any misconduct there.

The Intercept has been mining the group's archive to learn about the identities and activities of its members, and today, they revealed that CBP Chief Carla Provost was an active member of I'm 10-15 for some years, and posted more than once to it. While Provost's posts are innocuous, her presence on the group suggests that the CBP's official claims to be surprised at the group's existence and character were not entirely truthful.

Provost is not the only high-ranking CBP official who was also a member of I'm 10-15, and some CBP officials' social media activities were less benign that Provost's. For example, Border Patrol Calexico supervisor Tom Hendricks, a 20+ year veteran of the service, posted a meme depicting "a smirking Trump forcing Ocasio-Cortez's face into his crotch by the back of her neck."

Evidence of Provost's participation in the secret Border Patrol group comes as Ocasio-Cortez, along with Rep. Veronica Escobar, D-Texas;, Rep. Rashida Tlaib, D-Mich.; and Rep. Ayanna Pressley, D-Mass., head into a hearing with the Committee on Oversight and Reform and the inspectors general of DHS and the Department of Health and Human Services on Friday to discuss their recent visit to detention centers along the border.

As both ProPublica and The Intercept have reported, the lawmakers visit was a hot topic among "I'm 10-15" members, who discussed throwing burritos at the members of Congress or, in the case of one El Paso-based agent, staging a "bang in" to relieve stress from their presence. In a statement to the press Wednesday, Rep. Elijah E. Cummings, chair of the oversight committee, said the Facebook group would be a topic of discussion at the hearing. The Maryland Democrat has opened an investigation into the group and, in a letter to Mark Zuckerberg, requested that the Facebook executive see to it that his company "preserve all documents, communications, and other data related to the 'I'm 10-15' group" including "log files and metadata."

Shortly after the Facebook group was revealed, CBP's Office of Professional Responsibility issued a public statement, citing Provost, saying that it had alerted the DHS inspector general's office and that an investigation had been launched. McAleenan later said that an unspecified number of individuals had been placed on "administrative duties" following the disclosures over the last week, while ABC News obtained an internal memo showing that CBP "was aware, as early as February 2018, of at least one private Facebook group that included 'inappropriate and offensive posts' by its personnel."

Border Patrol Chief Carla Provost Was a Member of Secret Facebook Group [Ryan Devereaux/The Intercept]