According to emergency scanner traffic, the helicopter was found by a Minnesota State Patrol trooper . The status and identities of the crew members is unknown.
Minnesota Gov. Tim Walz confirmed Thursday night that all three crew members had died.
Stearns County Chief Deputy Dan Miller addressed local media and confirmed the helicopter crashed at approximately 2:15 p.m., Central.
According to emergency scanner traffic, the helicopter took off from St. Cloud at about 1:55 p.m. and called mayday about nine minutes after takeoff. St. Cloud Mayor Dave Kleis said the helicopter took off from the St. Cloud Regional Airport.
"We do not have contact with the helicopter but we do not quite yet know what the situation is," Minnesota National Guard Master Sgt. Blair Heusdens said after the base lost contact with the aircraft. "We're working to figure it out."
The helicopter was "conducting a maintenance test flight that originated from St. Cloud, Minnesota," the tweet states.
Sky conditions at the time the helicopter took off were clear with 10-mile visibility, according to the National Weather Service's observations at St. Cloud Regional Airport.
All St. Cloud units were called to respond to the incident and many units were staged near the airport.
According to emergency scanner traffic, law enforcement was working to ping the location of passengers' cell phones in an attempt to locate the helicopter.
Minnesota State Patrol was called to bring in a helicopter to assist with the search.
Sheriff's deputies were actively investigating the scene as of 5 p.m. and was asking people to stay out of the area.
"Our first priority is the safety and well-being of our Guardsmen and our thoughts are with our soldiers and their families at this time," the Minnesota National Guard tweeted.
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