Five days after Muhammad Ali Sadpara, John Snorri, and Juan Pablo Mohr Prieto launched their summit bid on Winter K2, and more than 100 hours since they were last seen from base camp, the search for the missing climbers has effectively ended. A fourth climber, Ali’s son Sajid Sadpara, 22, descended Saturday to base camp in winds as high as 60 miles per hour after waiting overnight for the others. Their departure marks the bitter end of a season that on January 16 saw the first winter ascent of K2. “When I was putting the regulator on, the oxygen started to leak because it didn’t fit well,” Sajid Sadpara said. Sajid Sadpara believes they reached the summit and met an accident on the way down.