A U.S. mountain climbing instructor died and two American students were injured when the ice bridge they were crossing on an Argentina peak broke, plunging them into a crevasse, officials of the sponsoring organization said Monday.

Matthew Lizotte of Aspen, Colorado, 25, died Sunday while scaling 11,411-foot Mount Tronador in Argentina's Nahuel Huapi National Park, Whitney Montgomery, executive director of North Carolina Outward Bound School, told The Associated Press.

Two unidentified students were injured, including one with a fractured arm. The other suffered multiple fractures and a chest injury, but the student's "condition continues to improve," Montgomery said.

A third student was released without treatment from the hospital in San Carlos de Bariloche, a small city nestled in the Andean foothills and the jumping-off point for expeditions into the park.

All three are U.S. citizens, U.S. Embassy spokeswoman Mara Tekach confirmed. Neither the embassy nor Outward Bound would release the names of the students.

Larisa Beletzky, a spokeswoman for Nahuel Huapi National Park, said the four climbers, linked by a rope, fell more than 66 feet into a crevasse when an ice bridge they were crossing near the peak of the mountain suddenly broke.

Other instructors alerted their course director stationed in Bariloche, who then radioed park authorities. A five-person rescue team arrived to find Lizotte dead. A helicopter carried the other three students to safety, she said.

Lizotte, an Outward Bound guide since 2006, was one of three highly trained staffers leading a 72-day course in Patagonia with 11 students between the ages of 18 and 23, Montgomery said.

The expedition — which was about a third of the way completed — has been put on hold while authorities assess how the crew is handling the crisis, he added.

The North Carolina Outward Bound School, a charter of Outward Bound USA, said it will investigate the accident.