Just moments before the Pittsburgh synagogue shooting that left 11 people dead, the suspect is believed to have posted a final social media rant against a Jewish refugee settlement agency most people had never heard of, but which has increasingly become the target of right-wing rage and conspiracy theories.

"HIAS likes to bring invaders in that kill our people," Robert Gregory Bowers wrote on the platform Gab early Saturday. "I can't sit by and watch my people get slaughtered. Screw your optics, I'm going in."

The group, formerly known as the Hebrew Immigrant Aid Society, was founded in 1881 in a Manhattan storefront to assist Jews persecuted in Russia and Eastern Europe. HIAS is now among nine groups that contract with the State Department to help refugees settle in the United States, and it has recently clashed with the Trump administration over policies that have throttled the flow of such newcomers.

Analysts who follow the extreme right say the fixation some extremists have with HIAS appears to be fueled by a mix of anti-Semitism and the recent caustic rhetoric about an immigrant caravan trudging slowly toward the United States.

Specifically, they believe Bowers ascribed to the "white genocide" conspiracy, which holds that Jews are prominent among the forces seeking to destroy the "white race" by bringing in non-white people. The Gab.com account believed to be Bowers' includes several recent postings or re-postings critical of HIAS.