David Breashears, an avid climber who summited Mount Everest and made an IMAX documentary about it, has died at age 68. Breashears was found dead at his home in Massachusetts on Thursday, his business manager told the Associated Press. An exact cause of death was not given. Breashears was the first person to send live photos from the summit of the world’s highest peak in 1983, and two years later became the first U.S. citizen to summit twice, according to his website. In 1996, while filming his documentary about the mountain, he and his team stopped to help other climbers when a deadly blizzard, which killed eight people, struck on May 10. “He combined his passion for climbing and photography to become one of the world’s most admired adventure filmmakers,” his family said in a statement. After releasing his documentary, Breashears started a nonprofit called GlacierWorks to highlight the effects of climate change on the Himalayas through a combination of artistic visuals and science. He summited Everest a total of five times throughout his life.