A Saturday performance of the St. Louis Symphony was disrupted by demonstrators protesting the killing of Michael Brown, the black, unarmed teenager who was shot by a police officer in Ferguson, Missouri.

"Justice for Mike Brown is justice for us all," protesters sang, before asking the audience, "Which side are you on, friend? Which side are you on?"

The video, by The St. Louis American, shows that tensions still remain in Missouri. Remember, the shooting death of Brown led to days of violent protests over the summer.

The St. Louis Post-Dispatch reports the interruption lasted five minutes. The paper adds:

"SLSO publicist Erika Ebsworth-Goold said the protesters were paying members of the audience. She said they left the building peacefully."Before leaving, the protesters scattered red paper hearts over the edge of the balcony onto the main floor orchestra seats. They read, in part: 'Requiem for Mike Brown.' "Copyright 2016 NPR. To see more, visit http://www.npr.org/.