Officials say two Mayo Clinic employees flying to the University of Florida to harvest organs have been killed in a helicopter crash.

Mayo Clinic spokeswoman Kathy Barbour says the Jacksonville hospital employees left early Monday but did not arrive in Gainesville. Their names were not released because relatives hadn't been notified.

Federal Aviation Administration spokeswoman Kathleen Bergen says the helicopter crashed about 12 miles northeast of Palatka.

A message left for a Clay County Sheriff's Office spokesman was not immediately returned.

Bergen said she had been told neither the employees nor the pilot survived.

The National Transportation Safety Board also is investigating.

FAA records show the helicopter is owned by SK Jets. The St. Augustine company had no immediate information.