In separate incidents, two medical transportation aircraft went down in Ohio and Alaska–one rotor wing and one fixed wing. In total, all six of the flight crew members involved in the incidents are presumed dead. It’s not believed either aircraft carried patients at the time of the crashes.

On Tuesday, Ohio State Highway Patrol confirmed a Bell 407 operated by Survival Flight, Inc. crashed shortly before 7: 30 a.m. while en route to pick up a patient in Pomeroy, Ohio, located about an hour’s drive southeast of Columbus. Approximately three hours after the downed aircraft report, local authorities discovered the crash site in Zaleski, an area slightly northwest of Pomeroy. According to a report from Fox Carolina, investigators from the National Transportation Safety Board (NTSB) and the Federal Aviation Administration (FAA) are currently working at the crash site.

Later that same day, the U.S. Coast Guard (USCG) launched a search for a missing King Air 200 flying from Anchorage, Alaska to the remote town of Kake. Operated by medical transportation company Guardian Flight, the crew was scheduled to pick up a patient upon arrival. The USCG is assisted by municipal fire and rescue departments as well as civilian vessels in the area, according to a report from the Navy Times. Although airplane wreckage was found about 20 miles from Kake, the USCG hasn’t confirmed whether it belongs to the missing King Air. As a precaution, Guardian Flight grounded its entire fleet until the root cause of the crash is determined.