Supporters of the fatally shot Missouri teen Michael Brown interrupted a St. Louis Symphony Orchestra performance at Powell Symphony Hall with peaceful protests on Saturday.

The disturbance happened during the orchestra’s performance of “German Requiem” by Brahms. Protesters in the upper balcony unveiled three banners with handwritten messages and artwork in memory of Brown. Other protesters stood up in the lower seating sections and sang a tribute to the teen that was set to Brahms’ piece.

The three banners can be seen in the video. One says, “Racism Lives Here,” with a drawing of a city skyline, presumably of St. Louis. Another says, “Requiem For Mike Brown: 1996-2014.” The final banner has a sketch drawing of Michael Brown’s face with his name and the years he was alive.

The song began with a few singing, “Justice for Mike Brown is justice for us all.” The rest of the protesters joined in for the refrain of the song, which repeated, “Which side are you on?”

Much of the rest of the audience clapped and cheered as the protesters sang for about a minute and a half. Some looked shocked and confused at the interruption of the orchestra.

Symphony publicist Erika Ebsworth-Goold told KMOX-TV that the protesters were ticketed members of the audience, not intruders, and “had lovely voices.”

After finishing the song, the protesters and supporters of Michael Brown chanted, “Black lives matter,” before they left the symphony hall.

St. Louis Police said they received no calls about the demonstration. Hundreds have been arrested during the two months of protesting in Ferguson after Michael Brown was shot by police officer Darren Wilson, however none were arrested after this particular musical disruption.