ARLINGTON, Va. (AP) — A county in northern Virginia pulled its officers out of the District of Columbia Monday night after they played a supporting role in clearing protesters from a park outside the White House so the president could walk to a church for a photo opportunity.

The Arlington County Board issued a statement Monday night saying its officers were used “for a purpose not worthy of our mutual aid obligations.”

Arlington officers joined a team of federal law enforcers using chemical agents and flash bangs to forcibly remove a large group of peaceful protesters from Lafayette Park.

 That cleared a path for President Donald Trump, who had just issued a statement from the Rose Garden vowing to crack down on protesters, to walk from the White House over to St. John’s Church, which had been damaged in earlier protests. Trump then posed with a Bible for a few minutes.

County Board Chair Libby Garvey said on Twitter she’s “appalled” that the mutual aid agreement was abused “for a photo op.”

D.C. Mayor Muriel Bowser, for her part, said Tuesday that the District of Columbia never put out a call for mutual aid.

“I might suggest their officers shouldn’t have been there in the first place,” Bowser added.

In a phone interview, Garvey said the aid request came from U.S. Park Police, and that the agencies have provided aid to each other routinely over the years. She said Arlington Police were helping in the District Saturday and Sunday without incident.

What was unacceptable Monday, she said, was using officers to facilitate “a press op.”

In Richmond, Virginia Gov. Ralph Northam said he rejected a federal government request to send the Virginia National Guard to the District in part because the troops were not requested by Bowser and because he didn’t believe in the mission.

“I am not going to send our men and women in uniform of a very proud National Guard to Washington for a photo op,” he said at a news conference Tuesday.

United States Park Police Acting Chief Gregory Monahan said in a statement Tuesday afternoon that officers used smoke canisters and pepper balls to quell protesters, but did not use tear gas as was widely reported.

While most reports described protesters as largely peaceful, Monahan said Park Police responded to clear the park only after protesters threw “bricks, frozen water bottles and caustic liquids” at police. He also said “officers found caches of glass bottles, baseball bats and metal poles hidden along the street.”

He said Park Police made no arrests and “will always support peaceful assembly but cannot tolerate violence to citizens or officers or damage to our nation’s resources that we are entrusted to protect.”

In a statement issued Tuesday evening, Arlington County said its officers “did not unholster their batons or fire rubber bullets or tear gas at the protesters” during the Lafayette Park event. “They used their presence to push protesters back. After the initial push back, our officers were replaced and returned to the staging area.”

Lafayette Park is under federal control, and as such provided the Trump administration an opportunity to demonstrate the aggressive moves Trump said should be taken to deal with demonstrations nationwide that have veered from peaceful to violent.

But Bowser expressed criticism at her news conference of the use of force to clear protesters under such circumstances.

“I didn’t see any provocation ... especially for the purpose of moving the president across the street.” she said.

Metropolitan Police Department Chief Peter Newsham said the city was not informed of the presidential movement until right before it happened. Newsham said his officers were not involved in moving the protesters out of Trump’s way.

Members of northern Virginia’s congressional delegation were also critical of the tactics. Democrat Gerry Connolly wrote a letter to the Secret Service on Tuesday asking for documents to explain their decision-making process. And Democrat Don Beyer, whose district includes Arlington County, called Trump’s response to the protesters “naked authoritarianism.”

“Unleashing state violence against peaceful American demonstrators and journalists to create a photo op is a violation of the President’s oath to defend the Constitution and a betrayal of everything this country stands for,” Beyer said.