Westbound lanes of Highway 58 near Hart Flat are shut down due to a big rig rollover. 

A big rig hauling hay overturned just before 4:30 a.m.Thursday. The California Highway Patrol says the truck overturned east of Hart Flat.

Officials with the CHP's Bishop office say the lanes could be shut down until at least 8 a.m. due to cleanup. 

No injuries have been reported.