Sig-Alert, I-10, Upland 8:26 a.m.

Three cars burst into flames following a four-car crash on the westbound 10 Freeway, forcing a complete closure of freeway. The crash was reported on the westbound 10 just west of Mountain Avenue at 8:26 a.m.
CHP officers said three vehicles were fully engulfed in flames, but it was unknown if anyone was injured, said Officer Albert Graciano. Both sides of the freeway were expected to remain closed until the fires were extinguished. Officers plan to then reopen the slow lane and shoulder on the eastbound side to move traffic through the area. Westbound lanes will also be reopened at that time. A Sig Alert that had been issued was canceled at 9:54 a.m.