One climber died and two others were injured when an expedition up North America's tallest mountain went awry, the National Park Service reported Wednesday.

Lynne Salerno, 31, of Anchorage, died at the 19,500-foot level of Mount McKinley, just short of the 20,320-foot summit, suffering from apparent exposure and hypothermia, mountaineering ranger Scott Gill said from the ranger station in Talkeetna.The expedition's assistant guide, John Schweider, 29, of Denver, took a bad fall and suffered severe head injuries, and officials dispatched a helicopter to pluck Schweider from the 17,200-foot level where other mountaineering rangers were attempting to stabilize him, Gill said. Another climber in the same party was suffering from frostbite.

The expedition was attempting to conquer McKinley in temperatures of 30 degrees below zero with blowing winds, Gill said, noting that rangers aren't sure exactly what caused Salerno's death.

Salerno is the first climber to die on McKinley during this year's brief two-month climbing season that began this month. More than 50 climbers have died on the mountain over the years.

The expedition ran into trouble late Tuesday or early Wednesday, but the first calls for help could not be radioed out until late Wednesday morning, Gill said.

Vern Tejas, perhaps the foremost McKinley guide, was leading this expedition, Gill said. This year, Tejas became the first person to successfully climb McKinley alone in the winter.

Salerno was director of a physical therapy clinic.