The rock group playing at the Altamont Speedway Free Festival in 1969 when a man was killed by a Hells Angels motorcycle club member was The Rolling Stones. The tragic incident occurred during their performance of "Under My Thumb." It was a chaotic event marked by numerous security and logistical issues, and the Hells Angels were hired as security for the concert. Unfortunately, their presence resulted in violence and clashes with concertgoers, culminating in the tragic death of a young man named Meredith Hunter. This event is often cited as the end of the "peace and love" era of the 1960s.