The FBI plans to see the nationwide investigation into the Jan. 6 Capitol insurrectionist through "to its conclusion," the bureau's director Christopher Wray said in an NPR interview on Thursday.

What he's saying: "We intend to see this to its conclusion, no matter how many people it takes us to devote to it, no matter how long it takes us to do it," Wray said. "If we have the evidence to charge somebody and they committed a crime on that day, I expect them to be charged."

• Flashback: Wray called the Capitol attack a case of domestic terrorism in early March.

"You know, I was appalled that something like that could happen in this country and determined to make sure that it doesn't happen ever again," he told NPR on Thursday.

• "We have doubled the number of domestic violent extremists investigations we've had since where they were when I started as director, and we were up to about 2,000. And that was before the Jan. 6 siege. So I expect the numbers to be even higher this year."

The big picture: The FBI has so far arrested more than 300 people for their roles in the Jan. 6 attack.

• On Thursday, the agency released footage of assaults on federal officers during the siege.
• Racially motivated violent extremism is the bureau's "top threat priority level," Wray said.

On the Atlanta-area shooting earlier this week, Wray said: "The FBI is supporting state and local law enforcement, specifically APD, the Atlanta Police Department, and the [Cherokee County] Sheriff's Office. So we're actively involved, but in a support role."