A regional carrier jet ran off a runway at San Antonio International Airport after landing on a flight from Los Angeles.
Chicago-based United Airlines spokeswoman Megan McCarthy says none of the 52 passengers and four crew members on the United Express jet were injured. They were bused to the terminal.
McCarthy says United will work with SkyWest Airlines, the operator of the regional carrier, to try to determine what caused the aircraft to leave the runway.
San Antonio airport spokesman David Hebert says in a story on the San Antonio Express-News Web site that the plane appeared to be having some mechanical difficulties.
The accident closed the primary runway at the airport for about two hours. Its other runway was already closed for construction.