A motorcyclist was killed during a crash Sunday on San Gabriel Canyon (39) Road, near Mile Marker 23.11 in Glendora, officials said.
The crash occurred at about 7:26 a.m., the California Highway Patrol reported.
The motorcyclist was pronounced dead at the scene, the CHP said.
A Sigalert was issued at 8:25 a.m. shutting down the northbound and southbound lanes of traffic for three hours.
No other information was immediately released.