TWO HARBORS, Minn. (WCCO) — A New Hope man was killed in a scuba diving accident in Lake Superior Saturday afternoon, according to the Lake County Sheriff’s Office.

Authorities say 42-year-old Aaron Timmerman was diving with a group at the Madeira shipwreck site near Split Rock Lighthouse on the north shore. At one point, he came to the surface and signaled for help, but sunk again before others could reach him.

Later, they found him unresponsive on the bottom of the lake and brought him to the shore where they began CPR. He was transported by helicopter to Gooseberry Falls State Park, but responders pronounced him dead at the landing site.

The Lake County Medical Examiner is working to determine the cause of death.