ORINDA -- The center bore of the Caldecott Tunnel was shut down for about 30 minutes Wednesday morning after a three-car crash amid the morning commute, according to the California Highway Patrol.

A sig alert issued by the CHP was lifted at 8:30 a.m. The crash before 8 a.m. shut down the center bore, causing delays in westbound traffic.

The CHP reported that the involved cars and emergency response vehicles blocked the center bore, which is one of three tunnels connecting Contra Costa and Alameda counties.

David DeBolt covers breaking news. Contact him in Richmond at 510-262-2728. Follow him at Twitter.com/daviddebolt.