A small group of Proud Boys were attacked at Chicano Park, because they wanted to show the American flag in the park and peacefully argue with socialists. The May Day 2019 march was planned to end in Chicano Park. Instead the ran into members of the Chicano Park political cult, who end up violently attacking them as the march begins to arrive at the park. The San Diego Police Department had to pepper-spray some of the radical, anti-American Chicanos and their extreme socialist allies in order to subdue them.
This was at the time a brand new Proud Boy chapter in San Diego. Not sure that they were even aware of what Chicano Park was like until they walked into this situation. They had just heard that the May Day March was ending there.
This clip combines the video by the Proud Boys with that of someone on the Chicano side. The Proud Boy with the beard was wearing a body camera. Between 5:46 and 15:27 its is Proud Boy audio overlaid on Chicano video. The first part is Proud Boy audio/video and the end is Chicano audio/video.