WASHINGTON, June 4 (Reuters) - Thousands of National Guard troops and federal officers in riot gear and masks ringed the White House and monuments in the US capital this week, evoking comparisons to an occupying force.

Washington Mayor Muriel Bowser on Thursday (Jun 4) said she wants most of them out of her district of 700,000 residents. But her powers are limited.

Like cities countrywide, the US capital has been rocked by a week of protests against police brutality and racism following the death of George Floyd, a black Minneapolis man who died after a white police officer knelt on his neck.

Shops and offices in DC and nearby areas were hit by nighttime vandalism and looting after peaceful demonstrations last weekend, prompting Bowser to impose a 7pm curfew on Monday and Tuesday.

The Democratic mayor told reporters she is fine with the DC National Guard helping to keep order. But she is examining all legal options to reverse the Trump administration's deployment of forces from elsewhere.

"We want troops from out-of-state, out of Washington, DC," Bowser said during a press conference on Thursday.

Several hundred active-duty troops from the 82nd Airborne Division who were sent to the DC area are expected to start returning to their home base in North Carolina, a US official said on Thursday.

Some 3,300 national guardsmen are in DC or en route from Florida, Indiana, Maryland, Missouri, Mississippi, New Jersey, Ohio, South Carolina, Tennessee and Utah, according to the National Guard.

The prospect of active-duty soldiers on the streets of the capital has alarmed former military officers.

"Every active-duty troop that participates in this thing should resign, should leave the military," said Harry Wiggins, a retired Army major, who on Thursday was carrying a staff with an American flag flying upside down, an international sign of distress, several blocks from the White House.

Bowser also questioned the command of hundreds of armed officers from nearly a dozen federal agencies, including Customs and Border Protection, the Bureau of Prisons and the Transportation Security Administration, who have been posted outside government buildings and on DC streets this week.

Some of the officers wore uniforms with no discernable insignia, raising questions about their identity and mission.

"We are concerned about the increased militarization and lack of clarity that may increase chaos," the top Democrat in Congress, House Speaker Nancy Pelosi, wrote on Thursday in a letter to Trump.