The news comes from The Blaze while referring to a Twitter video that captured the scene. A Children's Choir was performing The US National Anthem in the US Capitol when they were told by security (or police) to stop during the third verse. According to Christina Chapman Hefferman, believed to be affiliated with the choir, the performance was seen as offensive or as a protest.
Source: The Citizen Free Press Twitter screenshotChristina posted the video on her Facebook. She clarifies that their guide had approached the choir director before the end of the third verse. She also stated that the performance was stopped as it might have offend someone / caused issues. Christina also adds that the choir performance was approved on multiple levels.
What can I say? Imagine having a problem listening to the US National Anthem in the US Capitol (no less).