Attorney General Merrick Garland said Monday that the Justice Department was pouring resources into its effort to stop domestic violent extremists and that those who attacked the United States would be brought to justice, in a speech commemorating the 26th anniversary of the Oklahoma City bombing.

As a young Justice Department official, Garland led the investigation into the 1995 attack on the Alfred P. Murrah Federal Building, the worst domestic terror attack in U.S. history. Timothy McVeigh, an Army veteran who hoped to use violence to spark an anti-government revolution, was ultimately convicted of using a massive truck bomb to destroy the federal building and kill 168 people, including 19 children.

"Although many years have passed, the terror perpetrated by people like Timothy McVeigh is still with us," Garland said. "The Department of Justice is pouring its resources into stopping domestic violent extremists before they can attack, prosecuting those who do, and battling the spread of the kind of hate that leads to tragedies like the one we mark here today."

Garland delivered his remarks amid the Biden administration's ongoing efforts to combat domestic extremism in the wake of the deadly Jan. 6 attack on the Capitol by a pro-Trump mob that included members of anti-government militias and other right-wing extremist groups.

An intelligence report delivered to Congress last month warned that extremist groups pose a rising threat, with extremists who are motivated by race more likely to attack civilians, and members of anti-government militias more likely to target law enforcement and government buildings and employees.

"Those of us who were in Oklahoma City in April 1995 do not need any warning," Garland said. "This memorial is a monument to a community that will not allow hate and division to win."

The Justice Department's sprawling investigation into the Jan. 6 attack represents the administration's most visible effort to combat domestic extremism.

That effort gained ground Friday, when Jon Ryan Schaffer, a member of the Oath Keepers militia, pleaded guilty to assault charges and agreed to cooperate with the government inquiry.

Schaffer, 53, is the first defendant charged as part of the investigation to plead guilty, and his cooperation could help prosecutors pursue conspiracy cases against other assailants.