The Picayune Rancheria of Chukchansi Indians were planning to build a fuel station, smoke shop, and travel center at the intersection closest to the casino.
However, construction workers Wednesday morning found what is believed to be a fragment of a human bone.
Experts from Fresno State were notified and several agencies are now investigating-- including the Madera County Sheriff's Office.
The Chukchansi Tribal Chairwoman said they are stopping construction until they have a better understanding of what was found.