Daniel Burns told the Reno Gazette-Journal the governor was "coherent, alert and resting" at Renown Regional Medical Center where he was expected to remain Tuesday night.
Burns said Gibbons, 65, was helping to break a young horse at a ranch near Pyramid Lake when he was thrown late Tuesday afternoon.
The extent of his injuries was not immediately known but Gibbons was said to be in pain though he was able to move his arms and legs
Elected governor in 2006, Gibbons was defeated in the GOP primary in June by Brian Sandoval.
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