FORT COLLINS, Colo. -- A New Year's Day avalanche killed two men from Iowa who were snowmobiling near Rocky Mountain National Park, and a snowshoer was missing and presumed dead after another avalanche in Utah, officials said.

Forecasters warned that heavy snowfall and high wind during the weekend made conditions hazardous in mountainous areas of both states.

A blizzard had been moving through the Colorado mountains near Trap Lake and Cameron Pass where the two snowmobilers were caught in the avalanche Sunday morning, said Larimer County Sheriff's spokeswoman Eloise Campanella.

Seven people were caught in the slide, but five escaped, Larimer County sheriff's Sgt. Kevin Johnston said.

The victims were identified as Jacob Kroeger, 25, of Stockton, Iowa, and Gabriel Medina, 32, of Wilton, Iowa.

Campanella said the coroner ruled the men died from asphyxiation, due to compression of chest, due to obstruction of airway by snow.

The two victims were confirmed dead a couple of hours after the slide, Campanella said.

The avalanche was about 165 feet wide and more than 820 feet long, officials said.

The area around Cameron Pass is popular with snowmobilers and skiers. On Dec. 29, 2000, a snowboarder was killed in an avalanche at South Diamond Peak. Another avalanche killed a Colorado State University student who was skiing near the pass Dec. 14, 1999.

Cameron Pass is approximately 75 miles west of Fort Collins, where Colorado Highway 14 crosses the Continental Divide.

Including the two snowmobilers killed Sunday, at least four people have died in avalanches in Colorado this season.

In Utah, the dangerous conditions on the slopes Sunday forced rescue teams to hold off resuming their search for a snowshoer missing after an avalanche in Provo Canyon.

Marshall Higgins, 33, of Salt Lake City was caught in a slide Saturday afternoon near Emerald Lake and was presumed dead, Utah County Sheriff's Sgt. Spencer Cannon said. A friend with Higgins was able to ride out the slide and call for help. Rescue teams searched for nearly five hours Saturday before conditions became too dangerous.

A 16-year-old snowboarder who also was reported missing Saturday in a nearby Utah canyon was spotted by a helicopter pilot Sunday morning and rescued.

"He was very smart and built a snow cave," said Laura Schaffer, a spokeswoman for Snowbird ski resort. She said the teenager, visiting from California, had been snowboarding at the resort but had gone outside its boundaries.

The Utah Avalanche Center reported Sunday that conditions were still dangerous in the region, with dozens of slides recorded.

"The storm snow, water totals and strong winds have all conspired to make it downright dangerous out there," wrote forecaster Craig Gordon.