Published: Jun 25, 2013 10:26 AM EDT

DADE CITY, Fla. (AP) - The Florida Highway Patrol says the southbound lanes of Interstate 75 are now open following two crashes involving three tractor-trailers and a passenger near Dade City.
    
The FHP says the crashes happened around 5 a.m. Tuesday.
    
The agency says one man was airlifted to a hospital with serious injuries.
    
Investigators are trying to find out why the crashes occurred. The road was closed for about four hours and motorists were diverted to State Road 40.

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