WALNUT CREEK -- A man suffered major injuries after he was hit while trying to retrieve a tarp that had fallen out of his car Friday morning on northbound Interstate 680, according to the California Highway Patrol.

The collision was reported around 11:49 a.m., when a man in the middle lanes along I-680 near the Ygnacio Valley Road off-ramp was hit by a passing truck that had a trailer attached to it, the CHP said.

All but one lane along northbound I-680 was temporarily shut down while emergency crews worked to clear the area.

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