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Motorcyclist killed in 10 Freeway accident near San Dimas

Heavy backup is seen on the westbound 10 Freeway near San Dimas after a fatal motorcycle accident Monday, Sept. 9, 2013.

September 9, 2013 12:00:00 AM PDT
A motorcyclist was killed in an accident involving a big rig on the westbound 10 Freeway near San Dimas on Monday.

The accident happened shortly before 4:30 a.m. The motorcyclist was down under the big rig, and was later pronounced dead.

All lanes were fully reopened by about 7:10 a.m. At one point, the accident prompted a full closure of the freeway. Lanes gradually reopened, but caused a heavy backup out of Ontario.