The number of U.S. mass killings linked to extremism over the past decade was at least three times higher than the total from any other 10-year period since the 1970s, according to a report by the Anti-Defamation League. The report, provided to The Associated Press ahead of its public release Thursday, also found that all extremist killings identified in 2022 were linked to right-wing extremism, with an especially high number linked to white supremacy. “It is not an exaggeration to say that we live in an age of extremist mass killings,” the report from the group’s Center on Extremism says.