A U.S. Air Force major was arrested Wednesday at the Capitol as he called for the impeachment and removal of Donald Trump.

Maj. Jason Watson, an active-duty service member, was arrested by Capitol Police after his remarks at an event organized by the Removal Coalition, a group that lobbies members of Congress to impeach Trump, according to NBC News. He was accompanied by Rep. Al Green (D-Texas), who has introduced several articles of impeachment against Trump.

“I’m here with him because Rep. Green is the only member of Congress that has demonstrated the courage and conviction to force a vote on articles of impeachment,” Watson said at the event. “If Congress followed his example, we could remove the entire Trump administration, but Congress remains unconvinced of the urgency and necessity for them to honor their oaths, so we must persuade them with our unrelenting, uncompromising civil resistance.”

“When the president of the United States orders military action against foreign countries — absent an emergency scenario where American interests are under imminent dire threats, as was done with Venezuela, Cuba and Iran — that’s an unconstitutional usurpation of Congress’ authority and a violation of the War Powers Clause,” Watson added.

“These violations resulted in the deaths of 13 service members and injuries of hundreds more. For this, the president and vice president must be impeached, convicted and removed,” he said.

Capitol Police said in a statement that it “is generally against the law for the public to demonstrate on the House Steps unless they are with a Member of Congress.”

“Yesterday afternoon, a man was escorted to the House Steps by a Member of Congress,” the statement said. “When the Member of Congress left the area, our officers gave the man lawful orders to stop the illegal demonstration or he would be arrested. The man refused our lawful orders.”

Watson was arrested on charges of Crowding, Obstructing, and Incommoding, Capitol Police said.

“He stood for impeachment of the president on the Capitol Grounds, and thereafter he walked up the steps where he was arrested, and he was taken away,” Green said of Watson.

“This is the kind of courage necessary to inspire others to understand that liberty and justice for all that we pledge allegiance to is something that we can make real. It’s more than an ideal. It is something that can be real for every person in this country if we but only have the courage to take the stand that Maj. Watson took,” the congressman added.

At the time of the protest, Watson was on leave from his commission post as a logistics readiness officer in Poland.

Active-duty service members are prohibited from engaging in partisan political activities, especially while in uniform. Those who do can face criminal or administrative punishment, such as imprisonment, loss of pay, or dishonorable discharge, according to Military Times.

“Service members must comply with all laws, regulations and policies governing conduct and the wear of the uniform,” an Air Force spokesperson said. “As commanders verify inappropriate actions, they are responsible for taking the necessary administrative and disciplinary actions to hold service members accountable.”