Violence erupted at a concert at North Park Observatory in San Diego, California, on the night of June 7, after a man jumped on stage to attack rapper XXXTentacion during a show.

XXXTentacion later came back on stage to explain to the crowd that the concert had to be cancelled, but said that he would make it up to the crowd with a free show.

Shortly after the attack, concert-goers began chanting: “F*** Rob Stone,” in reference to a rapper that XXXTentacion is reported to have a rivalry with.