Mark Pitcavage, a senior research fellow at the Anti-Defamation League’s Center on Extremism, said he’s less concerned about organized attacks on federal or state capitols — though he agreed those should be heavily guarded on Inauguration Day — than he is about individuals or small extremist groups carrying out plots or shootings in the next two weeks.

“There’s more of a danger of loose cannons going off and deciding to do something,” Pitcavage said.

It’s unclear whether Wednesday’s attack was led by any particular organization or individuals, but participants in the mob included people sporting insignia from the Oath Keepers and Three Percenters, two of the most well-known national extremist groups.

Chris Hill, leader of the III% Security Force, an extremist group in Atlanta, said he’s been contacted by several people interested in joining groups like his since the Capitol takeover. (The Three Percenters are a loosely-affiliated collection of armed extremist groups named for the myth that only 3 percent of Americans took up arms against the British during the Revolutionary War.)