The Department of Justice has charged more than 150 people and identified hundreds more as suspects in the violent assault on the U.S. Capitol by supporters of former President Donald Trump.
"We are committed to seeing this through no matter how many people it takes, how many days it takes us or the resources we ... need to get it done," said Steven D'Antuono, the assistant director in charge of the FBI's Washington Field Office.
The investigation update, just shy of three weeks since the riot, comes as the U.S. Congress moves forward with an article of impeachment against Trump, whom Democrats and some Republicans accuse of having incited the deadly Jan. 6 event.
The acting U.S. attorney for Washington, D.C., Michael Sherwin, told reporters that the investigators have opened over 400 subject case files so far, although in some instances, authorities are still working to pin down the identity of the suspect.
Sherwin said investigators are working off of tips from the public, in some instances provided by family members or friends of the suspects. As investigators gather more evidence, including from grand jury subpoenas and search warrants, he said prosecutors are looking to build more complex cases with more significant charges.
"Everyone is all-in on these cases," Sherwin said.