CORONA (CBS)  — A 48-year-old Nevada woman suffering from some type of medical emergency fell to her death from a freeway overpass on southbound Interstate 15, according to the county coroner.

Maria Estrada of Henderson, Nev., fell about 60 feet into a drainage channel from an overpass about 30 feet south of Temescal Canyon Road near Corona shortly after midnight, the coroner said.

Estrada was airlifted to Riverside Community Hospital, where she was pronounced dead at 6:57 a.m., according to the coroner.

A CalFire spokeswoman said that she had some sort of medical emergency, but other details concerning the cause of her death were not immediately clear.

The California Highway Patrol temporarily closed lanes on the southbound 15 for an investigation, but the freeway was reported reopened at 1:28 a.m.

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