U.S. agencies warn of potential attacks by extremists tied to the midterm elections

U.S. security agencies have issued a heightened threat advisory, warning of a potential attacks on political candidates, election officials and others. The alert came Friday, the same day that House Speaker Nancy Pelosi’s husband was attacked in their San Francisco home.

NPR has obtained the bulletin issued by the Department of Homeland Security, the FBI, the National Counterterrorism Center, and the U.S. Capitol Police.

Attacks conducted by lone actors pose the most plausible threat to potential targets, the bulletin warned. The risk of violence is fueled by an increase in domestic violent extremism, and those carrying out the attacks would likely do so for ideological reasons.