Authorities have released the name of a scuba diver who died Saturday afternoon while exploring the Madeira shipwreck near Split Rock Lighthouse on Minnesota’s North Shore. The Lake County Sheriff’s Office says witnesses saw 42-year-old Aaron Timmerman of New Hope “surface and call for help” but no one could get to him before he went under. Fellow divers brought Timmerman up from the bottom of Lake Superior but were unable to revive him. Investigators have not disclosed cause of death, but one report indicates Timmerman was taking an instructional class at the time.