CONCORD (KRON) — Emergency crews responding to a rollover collision involving two cars has blocked the left lane of Interstate Highway 680 near Concord.

CHP Officer John Fransen said officers responded at 1:28 p.m. to northbound lanes of Highway 680 on a report of a collision north of Willow Pass Road.

A red pickup truck traveled off of the roadway and rolled over several times before landing in a ravine, according to Fransen.

An ambulance has been called to the scene, but Fransen said he did not know how many people are injured or the extent of their injuries.

Stay with KRON as this story develops.

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