A group allied with the decentralized hacktivist collective Anonymous published what it claims are private phone numbers and email addresses for 22 Republican senators.
The move comes as part of a "Denouncement Day" effort Friday protesting Confederate memorials around the country.
"The Anon Journal" published the contact information with an invitation to call the senators and demand movement by the GOP against President Trump in the wake of his "both sides" comments about violence between white supremacists and counterprotesters at a white supremacist rally Charlottesville, Va., organized to protest the removal of a statue of Robert E. Lee.
"We need to let our Senators know, that it is imperative for them to take action now," reads the post.
GOP senators that have apparently had their contact information revealed by the group include Ben SasseBen SassePresident of newly recognized union for adult performers boosts membership Romney blasts Biden over those left in Afghanistan: 'Bring them home' Progressives breathe sigh of relief after Afghan withdrawal MORE (Neb.), Chuck Grassley (Iowa), James InhofeJames (Jim) Mountain InhofeTop Republican: General told senators he opposed Afghanistan withdrawal Austin, Milley to testify on Afghanistan withdrawal The Pentagon budget is already out of control: Some in Congress want to make it worse MORE (Okla.) and Dean HellerDean Arthur HellerTexas abortion law creates 2022 headache for GOP Heller won't say if Biden won election Ex-Sen. Dean Heller announces run for Nevada governor MORE (Nev.).
"Your constituents trusted you to keep the Executive Branch in check, yet with all this control, you have managed to fail us in the worst way possible," wrote the post, which says more senators information will be released shortly.
"Is that the legacy you want to leave behind for your grandchildren?"
Denouncement Day is advertised as a protest to "give everyone the opportunity to tear down symbols of hate that still stand in a country that denounces hate today" and is to take place Friday evening at a variety of Confederate monuments in the South, including the Lee statue in Charlottesville.