A weekend BASE jumping accident in a Utah canyon has killed two people, according to authorities. The Grand County Sheriff’s Office confirmed that one of the victims was Andy Lewis, an extreme athlete known for BASE jumping, a sport that involves parachuting after jumping from fixed objects such as cliffs, bridges or buildings. Several outlets report that Lewis was widely recognized after he appeared onstage during Madonna’s 2012 Super Bowl halftime show, which brought him broader public attention.

Reports describe the incident as occurring in a canyon setting, but they do not provide detailed information about what caused the jump to fail. They also do not specify the identity of the second victim in the material provided. One outlet additionally cites a medical study published in 2007 that estimated BASE jumping carries a substantially higher risk of injury or death than skydiving, underscoring the dangers associated with the sport.

Officials have not, in the included accounts, released further investigative findings or conclusions about the circumstances of the deaths.