IDAHO SPRINGS, Colo. — Rescue teams Wednesday evening called off their search for a father and son from Minnesota who went missing last week in the snowy Colorado mountains.

“It won’t continue on any official basis ever, unless we find some evidence that warrants us being out there,” Alpine Rescue Team spokesman Steve Wilson said of the search. “We feel that we haven’t left any stone unturned.”

Damian McManus, 51, and Evan McManus, 18, of St. Louis Park, were last heard from April 2 when one of them told a friend they were going to scale a peak. They had been hiking near Mount Evans about 35 miles  away from Denver.

Searchers aren’t sure if they were equipped for the wintry conditions.

Rescue teams received help from a military electronics investigation team that tracked cellphone signals from a campground. Based on those signals, authorities narrowed the search area to the south and southwest part of a campground near Mount Evans.

On Tuesday, more than 50 members of nine Colorado search and rescue teams worked in snow more than 3 feet deep in places and in thick timber on the mountainsides. They were assisted by a helicopter that searched key areas of the mountain between elevations of 10,000 and 14,000 feet.

Relatives of the missing men are in Colorado, but they have not taken part in the search because of the dangerous conditions. The rugged terrain has numerous trails that are slippery, rocky and covered in snow.

“It’s now been a week since they’ve been out there, and a lot of weather has happened out there in that week,” Wilson said.

Mount Evans is 14,250 feet high and has one of the highest paved roads in North America. The road closes at the end of summer, when weather conditions can quickly become treacherous.

The Echo Lake Campground, where their car was found, is at the base of the mountain.

High winds forced a helicopter to end its search early Monday, and the threat of avalanches prevented search teams from going into some areas.