(BOULDER COUNTY, Colo) — Three people are confirmed dead after two small aircraft collided mid-air in Colorado Saturday, authorities said.

Multiple 911 callers reported seeing two planes collide over Boulder County shortly before 9 a.m. local time, the Boulder County Sheriff’s Office said.

The aircraft collided and crashed near Vance Brand Airport in Longmont at 8:50 a.m., according to the Federal Aviation Administration.

The collision involved a single-engine Cessna 172 and a Sonex Xenos aircraft, a type of motor glider, the National Transportation Safety Board said.

NTSB investigating the Sept. 17, mid-air collision of a Cessna 172 with a Sonex Xenos aircraft near Longmont, Colorado.

— NTSB Newsroom (@NTSB_Newsroom) September 17, 2022

First responders found two separate crash sites near Niwot Road, the sheriff’s office said.

Two people were on board the Cessna 172, the FAA said. The sheriff’s office also said it confirmed two people were on board the plane, both of whom were found dead at the scene.

The sheriff’s office said at this time one person was confirmed to be in the aircraft, who was also found dead at the scene. The FAA said it is unknown how many people were on board the second aircraft.

The victims have yet to be identified, the sheriff’s office said. Once identified, their names will be released pending next-of-kin notification.

The FAA and NTSB are investigating the cause of the crash.

The roads near the crash sites will be closed amid the investigation, according to the Mount View Fire Department, which asked people to avoid the area.

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