(CBS SF / CNN) -- US Customs and Border Protection officials say they are investigating "disturbing social media activity" after a published report of a closed Facebook group for current and former border patrol agents that reportedly features jokes about migrant deaths, derogatory comments about Latina lawmakers and a lewd meme involving at least one of them.
The posts were "hosted on a private Facebook group that may include a number of CBP employees," according to Matthew Klein, assistant commissioner of CBP's Office of Professional Responsibility
The existence of the group "I'm 10-15" was exposed by the investigative reporting group ProPublica. CNN has not been able to independently access and review the Facebook group posts in question.
It is not clear how many group members are or were affiliated with the Border Patrol.
ProPublica claims it was able to link the participants in those online conversations to apparently legitimate Facebook profiles belonging to Border Patrol agents. Neither ProPublica nor CNN have been able to reach group members who made the postings.
ProPublica reports that the Facebook group's page boasts 9,500 members and says it was formed in 2016. It is unclear from the reporting how many members claim to be active agents. Posts feature comments about the death of a teen Guatemalan migrant in Weslaco, TX such as "oh well" and "if he dies he dies."
Another post encourages members to protest Monday's border visit by Reps. Alexandria Ocasio-Cortez and Veronica Escobar, saying they should "throw a 10-15 burrito" at them. A meme posted on the group site depicts Ocasio-Cortez in a lewd act with a detained migrant, according to ProPublica.
ProPublica reports that, in another thread, a group member suggests the photo of drowned migrant father and daughter could have been faked because the bodies were so "clean." "I have never seen floaters like this," the poster reportedly wrote, adding "could this be another edited photo. We've all seen the dems and liberal parties do some pretty sick things..."
A statement from US Border Patrol Chief Carla Provost said, "These posts are completely inappropriate and contrary to the honor and integrity I see — and expect — from our agents day in and day out. Any employees found to have violated our standards of conduct will be held accountable."
The report inspired outrage from Democrats in Congress.
Responding to the ProPublica report, Rep. Joaquin Castro, the chairman of the Congressional Hispanic Caucus, tweeted: "These agents don't deserve to wear any uniform representing the United States of America."
In another tweet, Ocasio-Cortez decries a "racist & sexually violent secret CBP Facebook group. They're threatening violence on members of Congress."
House Homeland Security Committee Chairman Bennie Thompson, a Democrat from Mississippi, said the report points to "clear and systemic problems that must be addressed immediately," within DHS and CBP.
"This Facebook group is beyond sexist and racist -- it is truly abhorrent and shameful, and there is no excuse for this depraved behavior," Thompson said. "The agents found to be responsible for these vile comments should no longer have the privilege of representing the United States of America in uniform."
ProPublica is a nonprofit news organization that produces investigative journalism.
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