The cause of the crash was not immediately known, Cerro Gordo County Sheriff Kevin Pals said. The crash site is about 15 miles west of Mason City. The helicopter was in the air for a very short time before it went down, Fred Buttrell, Med-Trans president and chief executive, said Thursday at a press conference in this city of about 30,000 about 120 miles north of Des Moines, Iowa. He began working for the company in September and previously had logged 2,700 flight hours as well as going through the Dallas-based company's training programs, according to press releases from the hospital and medical transportation company. Lair-Langenbau and Piehl were hospital employees since 19 while Grell was employed by Med-Trans, the hospital's helicopter service.

Pilot Gene Grell, nurse Shelly Lair-Langenbau, and paramedic Russell Piehl died.

CST in a farm field just north of Ventura, Iowa. The Mercy Air Med helicopter, affiliated with Mercy Medical Center-North Iowa here, was answering a call when it went down sometime around 9 p.m.

MASON CITY, Iowa - A medical helicopter flying from Mason City to Emmetsburg, Iowa, crashed in a field late Wednesday, killing all three people on board.

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