The suspect is believed to have fled the state, police said.
In-N-Out is banning employees from wearing face masks in certain states unless they get a doctor's note.
The National Park Service says the mask requirement is for areas the CDC identifies as high COVID-19 community level, which includes Yosemite.
The sudden end to the mask mandate has sparked much confusion leaving passengers wondering if they still have to wear a mask or not.
It comes as California state health officials plan to lift the guidelines for indoor mega-events statewide this Friday.
The CEOs of 10 airlines and cargo carriers have signed a letter to President Joe Biden saying he should end the transportation mask mandate and testing requirements for international travelers.