An Interior Department watchdog office will investigate law enforcement and security forces’ violent clearing of protesters from a square in front of the White House earlier this month.

The Interior Department’s U.S. Park Police and other forces released chemical agents and at times punched and clubbed a largely peaceful of crowd of demonstrators to drive the public from Lafayette Square on June 1, during nationwide protests over the police killing of George Floyd.

Three Democratic lawmakers — Sen. Ron Wyden of Oregon and Reps. Raul Grijalva of Arizona and Debra Haaland of New Mexico — had asked Interior Department Inspector General Mark Lee Greenblatt to investigate the actions that night of the Park Police, who oversee some of the nation’s most iconic national monuments.

Greenblatt agreed late last week, telling the lawmakers that Interior Secretary David Bernhardt had also asked for the review.

“Given the significance of the events, we have already begun collecting and reviewing information concerning the Park Police’s activities,” he told the Democrats.

The agency’s first task will be determining which of the many agencies was in charge of law enforcement in the square that night, Greenblatt said. That “adds complex and jurisdictional challenges” to the watchdog office’s work, he wrote.

Authorities have given at times conflicting accounts about who oversaw and ordered the forceful routing of protesters from Lafayette Square. Besides a range of law officers, the Secret Service and Attorney General William Barr were among those present at various times then.

Forces drove the crowd from the square shortly before President Donald Trump walked unannounced to an area nearby to pose for photos.

The administration has denied demonstrators were cleared out to make way for Trump. Bernhardt, the interior secretary, has said violent attacks by the crowd warranted clearing the protesters. Reporters and other witnesses and Democratic lawmakers say they saw little sign of that scale of violence by the crowd.

This story has been corrected to show first name of Sen. Wyden is Ron, not Roy.