Three people have been killed after two helicopters collided midair near McMinnville Municipal Airport in northwest Oregon, United States.

According to Yamhill County Sheriff Sam Elliott, emergency crews responding to the incident found the wreckage in a private farm field in a rural area near the airport, approximately 40 miles southwest of Portland.

One of the helicopters was carrying two people: a 22-year-old flight instructor from Texas, identified as Maddie Aasbo, and a student pilot from the United Kingdom whose identity has not been released pending notification of family members.

The second helicopter was carrying one person, identified as 38-year-old Tyler Delane Sturdevant, a pilot from Newberg, Oregon.

The collision occurred at approximately 2:15 p.m. local time. It was not immediately clear what caused the two aircraft to collide.

The small airport, situated on 650 acres (263 hectares), has two paved runways and remained open on Thursday, according to its website. It's partially bordered by homes and near the North American Aerospace Museum.

The Federal Aviation Administration (FAA) and the National Transportation Safety Board (NTSB) responded to the scene and are leading investigations to establish the circumstances surrounding the crash.

The NTSB identified the aircraft involved as a Robinson R-22 and an Airbus AS350.

The student pilot's identity remains undisclosed as authorities work with the British consulate and the Federal Bureau of Investigation (FBI) to notify the next of kin.

One of the aircraft was operated by Jerry Trimble Helicopters, a flight training school based at McMinnville Municipal Airport.

In a statement, the company confirmed that one of its helicopters was involved in the incident, expressing deep sorrow over the loss of life and extending its thoughts to the victims, their families and everyone affected.

Jerry Trimble Helicopters added that it was fully cooperating with investigators as they work to establish the cause of the collision.

Meanwhile, the Yamhill County Sheriff's Office appealed to members of the public to avoid the crash site to allow emergency responders and investigators to carry out their work.