Maryland Gov. Larry Hogan (R) stepped into a dispute in Montgomery County, calling Sunday for the county to allow police to display a donated “thin blue line” flag that is meant to show support for law enforcement, but also is associated by some with white nationalists.

“To outlaw these American flags from being hung in county buildings by law enforcement officers is outrageous and unconscionable,” Hogan tweeted.

A local man and his young son donated a homemade wooden American flag to a police station in Germantown a week ago. The flag — which includes a bright blue stripe in place of one of the flag’s standard 13 stripes along with the phrase “thin blue line” — has long been used to evoke the role of police in keeping order. The donation was meant as a show of respect for the risks taken by law enforcement and was presented in conjunction with National First Responders Day.

But the flag also has been used by the Blue Lives Matter movement, which is a pro-police effort to counter Black Lives Matter and its protests against police-involved killings of often unarmed black people.

After receiving the gift, Montgomery County police thanked the donor, who police identified as James Shelton, and said on Twitter last Wednesday that the flag would be displayed in the 5th District station.

The gesture generated immediate blowback from some in the county, with critics saying the flag excuses police violence against black residents. The flag, some noted, was seen along with Confederate flags at the white supremacist rally in Charlottesville in 2017.

Responding to the controversy, Montgomery County Executive Marc Elrich said Friday that the flag will not be displayed in any public space at the police department.

“The flag provides a symbol of support to some but it is a symbol of dismissiveness to others,” he said in a statement. “Under my administration, we are committed to improving police relations with the community and will immediately address any action that stands against our mission.”

Both angry and supportive responses followed. Critics included the police union, Montgomery County FOP Lodge 35.

“The working police officers of Montgomery County are highly offended by this act of outright disrespect for them and that flag which represents the sacrifices and dedication of police officers who daily risk their lives, health, limbs and own well-being in service to their community,” the union said in a statement.

Then on Sunday, the governor called on Elrich to reverse his “terrible decision” and apologize for it.

“We are proud to hang these Thin Blue Line flags in Government House to honor our brave law enforcement officers,” Hogan tweeted with a photo of himself in front of two of the flags.

But Elrich was backed up by others, including Maryland Del. Gabriel Acevero (D-Montgomery).

“This is not the American flag,” Acevero tweeted. “It’s a violation of the flag code that prohibits altering of the flag in this manner & an affront to the #BlackLivesMatter protests that I & others were a part of. Stop pandering & focus on police reform!”

Neither Elrich nor his spokesman replied to requests for comment on Sunday. Shelton, who donated the flags, could not be reached for comment.

Shelton and his son also donated a version of the wooden flag with a red stripe to Fire Station 31 on Darnestown Road in North Potomac. A spokesman for the Montgomery County Fire & Rescue Service said the department had not received any similar pushback and the flag is on display at the firehouse.