A foreign Marxist group behind decades of terrorist attacks has quietly embedded itself in American activism, an academic report finds.

Several groups leading pro-Palestinian protests in the United States have shared event spaces with the violent Popular Front for the Liberation of Palestine, echoed its narratives, or defended its members in recent years, according to a paper released Monday by George Washington University. The State Department designated the PFLP a foreign terrorist organization in 1997, and authorities have linked it to plane hijackings, deadly bombings, a 1972 mass shooting, a 2014 synagogue massacre, and further bloodshed during Hamas’s Oct. 7, 2023, invasion of Israel. The organization’s attacks have killed dozens of Americans globally.