Garland returned to the city where he oversaw the prosecution of McVeigh and his accomplice, Terry Nichols, in the April 19, 1995, bombing of the Alfred P. Murrah Federal Building that killed 168 people and left inured several hundred others.
"It is now 26 years since the bombing. And it is as surprising to me as it is to you that I am now the attorney general of the United States," Garland said in remarks on Monday. "Although many years have passed, the terror perpetrated by people like Timothy McVeigh is still with us. Just last month, the FBI warned of the ongoing and heightened threat posed by domestic violent extremists."
With his remarks coming three months after the violent riots at the U.S. Capitol and amid a wave of mass shootings, Garland vowed to fight further acts of terror.
"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 today," he said. "We must all stand together against them -- for the safety of our communities and for the good of our country."
Garland recalled receiving an "urgent report" while at his office at the U.S. Department of Justice on the night of the bombing before arriving in Oklahoma City two days later to survey the scene.
"Shattered glass and crumbled bricks were everywhere," he said. "It was night, but you would not have known it. Bright lights lit the site up like it was midday. The front of the Murrah building was gone. The parking lot across the street still held the cars that had been flattened by the blast."
Garland said that investigators never forgot the victims as they worked the case, noting that he carried a program for a service remembering them in his briefcase.
"Oklahoma City, you are always in my heart," he said.
McVeigh was sentenced to death and executed by lethal injection in 2001 and Nichols was sentenced to life in prison.
During his confirmation hearing in February, Garland referenced his work prosecuting the bombers, saying he would "supervise the prosecution of the White supremacists and others who stormed the Capitol on Jan. 6, a heinous attack that sought to disrupt a cornerstone of our democracy, the peaceful transfer of power to a newly elected government."