ANCHORAGE, Alaska (AP) An aircraft carrying 10 people across Alaska’s Norton Sound south of the Arctic Circle went missing Thursday afternoon and rescuers searched into the night for any sign of the aircraft.

The Bering Air Caravan was heading from Unalakleet to Nome with nine passengers and a pilot, according to Alaska’s Department of Public Safety. Authorities were working to determine its last known coordinates.

Unalakleet is a community of about 690 people in western Alaska, about 150 miles (about 240 kilometers) southeast of Nome and 395 miles (about 640 kilometers) northwest of Anchorage.

The disappearance marks the third major incident in U.S. aviation in eight days. A commercial jetliner and an Army helicopter collided near the nation’s capital on Jan. 29, killing 67 people. A medical transportation plane crashed in Philadelphia on Jan. 31, killing the six people onboard and another person on the ground.

The Cessna Caravan left Unalakleet at 2:37 p.m., and officials lost contact with it less than an hour later, according to David Olson, director of operations for Bering Air. The aircraft was 12 miles (about 19 kilometers) offshore, according to the U.S. Coast Guard.

“Staff at Bering Air is working hard to gather details, get emergency assistance, search and rescue going,” Olson said.

Bering Air serves 32 villages in western Alaska from hubs in Nome, Kotzebue and Unalakleet. Most destinations receive twice-daily scheduled flights Monday through Saturday.

Airplanes are often the only option for travel of any distance in rural Alaska, particularly in winter.

The Nome Volunteer Fire Department said in a statement on social media that ground crews were searching across the coast, from Nome to Topkok.

“Due to weather and visibility, we are limited on air search at the current time,” it said. People were told not to form their own search parties because the weather was too dangerous.

In an update early Friday, the department said that “crews are still searching on the ground, canvassing as much area as possible,” but that “we do not have any updated information on the location of the missing aircraft.”

A U.S. Coast Guard airplane crew was expected to search the missing aircraft’s last known position. The National Guard and troopers were also helping with the search, according to the fire department.

It was 17 F (-8.3 C) in Unalakleet around takeoff, according to the National Weather Service. There was light snow falling and fog.

The names of the people on board weren’t yet being released.

Nome, a Gold Rush town, is just south of the Arctic Circle and is known as the ending point of the 1,000-mile (1,610-kilometer) Iditarod Trail Sled Dog Race.