CLAREMONT (CBSLA) — One man was killed Sunday morning as a result of a chain-reaction crash in Claremont.

About a dozen cars were involved in the deadly pile-up on the 10 Freeway at Indian Hills Boulevard.

The crash unfolded just after 2 a.m., spurring the temporary closure of all westbound lanes on the thoroughfare.

The exact cause of the collision is still under investigation.

However, reports have surfaced to suggest that a CHP patrol car was conducting a traffic break before that crash.

No further details were immediately available.