Noose found at National Museum of African American History in Washington

WASHINGTON, DC - SEPTEMBER 14: A combination of video screens, printed information, photographs, posters and other artifacts fill the '1968 and Beyond' History Galleries at the Smithsonian's National Museum of African American History and Culture on the National Mall September 14, 2016 in Washington, DC. Filled with exhibits and artifacts telling the story of the first Africans in the United States and their descendents, the 400,000-square-foot museum will open to the public on September 24. (Photo by Chip Somodevilla/Getty Images)

WASHINGTON — A noose was found at the National Museum of African American History and Culture in Washington, DC on Wednesday, the museum said in a statement. This is the second incident in the last week of a noose being found on Smithsonian properties.

“Today’s incident is a painful reminder of the challenges that African Americans continue to face,” museum Founding Director Lonnie Bunch said in a statement posted on Twitter. “This was a horrible act, but it is a stark reminder of why our work is so important.”

The US Park Police said it was investigating “a case of that nature,” but had no further details.

The museum was opened by President Barack Obama in September 2016.

On Friday night, a Smithsonian police officer reportedly found a noose hanging from a tree while conducting security checks on the grounds.