DC National Guard investigating actions by its low-flying helicopters during Monday night protests

The DC National Guard first announced the investigation on Tuesday, saying in a statement provided to CNN that its commanding general, Maj. Gen. William J. Walker, "directed an investigation into a June 1 low-flying maneuver conducted by one of our rotary aviation assets."

In a longer statement Wednesday, the Guard said that it is investigating the use of a "medical evacuation helicopter as part of the Joint Task Force DC operation."

The investigation is to ensure all the helicopters involved Monday "complied with applicable procedures and safety regulations," the Guard said.

"I hold all members of the District of Columbia National Guard to the highest of standards. We live and work in the District, and we are dedicated to the service of our nation," Walker said in a statement.

On Monday, crowds protested outside the White House over the death of Floyd at the hands of a police officer in Minneapolis. As the city curfew was about to go into effect at 7 p.m. ET., law enforcement began pushing back the crowd using tear gas, smoke canisters and rubber bullets. A spokesman for the Pentagon claimed to CNN Tuesday the National Guard did not fire tear gas or rubber bullets.

Well after the curfew, protesters were still out on the streets, and video captured by CNN showed a military helicopter hovering over a group of them, using its propellers to kick up strong wind and debris.

The tactic is a show of force and commonly used by the military in overseas combat zones to drive away targets from a specific area.

Some social media posts showed the Red Cross symbol displayed on the side of one UH-72 Lakota helicopter.

Residents also reported buildings vibrating from the helicopters being so close, and there were reports of some windows broken by the choppers as the wind they kicked up tossed debris from the streets.

Pentagon spokesperson Lt. Col. Chris Mitchell told CNN on Tuesday that "UH-72 aircraft were flying last night to provide observation of DC National Guard positions as they conducted civil unrest operations."

"They were not dispatched as part of any law enforcement operation," Mitchell added.

The Guard said its statement to CNN Tuesday that its "highest priority is the safety of our Citizen Soldiers and Airmen who support civil authorities as they perform their duties."

"This is our home, and we are dedicated to the safety and security of our fellow citizens of the District and their right to safely and peacefully protest," it added.