ROCHELLE, Ill. (AP) - Hospital officials say a pilot and two nurses were killed when a medical helicopter crashed in a field while traveling between two northern Illinois hospitals.

Rockford Memorial Hospital identified those killed as pilot Andy Olson and flight nurses Karen Hollis and Jim Dillow. In a news release Tuesday, officials at Rockford Memorial Hospital say they are grieving for "three heroes who dedicated their careers to serving others."

No patients were aboard when the helicopter went down Monday night in Rochelle, about 70 miles west of Chicago. A spokesman for the Rockford hospital says its helicopter was flying to pick up a patient at a Mendota hospital.

Federal Aviation Administration spokesman Tony Molinaro says the FAA is helping the National Transportation Safety Board investigate to determine what caused the crash.

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