The World War Two memorial in Washington was vandalised with bubbly soap and graffiti on Thursday, prompting vows from the ​US government to find the perpetrator.

The fountain bubbled over with suds, and ‌someone painted “Clean hands Dirty $” on one surface, splattering the area with red and green paint. Uniformed police and National Guard troops converged on the scene, which was cordoned off with yellow crime scene tape, keeping ​visitors away.

One investigator in plainclothes bent over the site of the graffiti, ​measuring the damage with a tape measure, Reuters pictures showed. Workers arrived ⁠to remove the graffiti, the Washington Post reported, citing Park Police officers at ​the site.

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Dedicated in 2004, the memorial features 56 granite pillars around the edge of an ​elliptical plaza on the National Mall as a monument to the 400,000 Americans who died and 16 million who served in the armed forces during the conflict, according to the National Park Service.

“The ​vandalism that occurred is an utter disgrace and will not be tolerated,” the ​Interior Department, which oversees the National Park Service, said in a statement. “Our US Park Police are on ‌the ⁠scene, and the investigation is ongoing. The public should know we will find the person responsible for this disgusting act.”

The Friends of the National WWII Memorial, a nonprofit group dedicated to preserving the memorial, called the vandalism “unacceptable,” saying the memorial was a “sacred place ​of remembrance.”

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“There are ​many places in our ⁠country for expression, debate, and disagreement. A national memorial honouring those who served and those who never returned home should never ​be used as a canvas for vandalism,” the Friends said in ​a statement.

The ⁠US role in World War Two is largely a matter of national pride and unity even in highly polarising times, though many Americans still debate whether the US should ⁠have dropped ​two atomic bombs on Japan to end the ​war.

The vandalism comes as US President Donald Trump has launched a personal and sometimes politically divisive campaign to alter memorials ​around Washington.

According to the National Park Service, the National World War II Memorial in Washington, DC was constructed between 2001 and 2004 and formally dedicated on May 29, 2004, during Memorial Day weekend. The Service claimed it opened to the public in April 2004.

The memorial is located adjacent to the Washington Monument, in the heart of the National Mall.