CONCORD -- Two power outages affecting some 1,500 customers were reported in north Concord and in the Clayton Valley area on Sunday evening, according to PG&E.

As of 6:30 p.m., about 400 customers in the Clayton Valley area were still without power, but crews were on site.

PG&E reported the first outage in north Concord along Port Chicago Highway at 5:36 p.m., with power lost to 1,055 customers. It was restored within an hour, said Jana Morris, a PG&E spokeswoman.

Crews are on site, but the cause of the outages has not yet been determined, she said.

Check back for updates.

Contact Catherine D. Jacobson at cjacobson@bayareanewsgroup.com or follow her at Twitter.com/CJacobsonWC.