Two prospects from the U.S. Ski Team were killed in an avalanche Monday while skiing near their European training base in the Austrian Alps.

The U.S. ski team said Ronnie Berlack, 20, and Bryce Astle, 19, died in the incident near the Rettenbach glacier near Soelden, the venue for the annual season-opening World Cup races.

Berlack, from Franconia, New Hampshire, and Astle, from Sandy, Utah, were part of a group of six skiers who were descending from the 3,056-meter Gaislachkogel when they left the prepared slope and apparently set off the avalanche. The other four skied out of the slide and escaped unhurt.

Officials in the Tyrolean region said an avalanche alert had been declared for the area after days of heavy snowfall and mild temperatures.

"Ronnie and Bryce were both outstanding ski racers who were passionate about their sport — both on the race course and skiing the mountain," U.S. Ski and Snowboard Association President and CEO Tiger Shaw said. "Our hearts go out to the Berlack and Astle families, as well as to their extended sport family. Both of them loved what they did and conveyed that to those around them."

Berlack grew up racing in New Hampshire and had been a student-athlete at Vermont's Burke Mountain Academy. He was named to the so-called development team for potential World Cup racers following two top-20 finishes at the 2013 U.S. national championships and a spring tryout camp.

Astle was invited to train with the development team this season after strong early season results, including two top-10 results at NorAm Cup races last month in Canada.

The tragedy has left the U.S. ski team "in shock," Alpine director Patrick Riml told The Associated Press in Croatia, Zagreb, where the American slalom team was preparing for a night race on Tuesday.

"We are all very close," said Riml, an Austrian who was born and grew up in Soelden. "We train a lot in Park City. We'll see how they handle the whole thing and how they react."

Riml added "it's a shock for everybody. Two great boys, great athletes, good skiers. They were fun to have around. We are all in shock, still. It's very tragic."

Berlack and Astle were part of a group of 10 skiers on the development team who gained experience in the Europa Cup and were preparing to race on the top-level World Cup.

"They all have the potential (to be on the World Cup)," Riml said. "These two boys were among the other eight boys who are our future. We believed in these guys, that's why we selected them."

Soelden has been the European base for the U.S. ski team since 2011.