YUBA CITY (CBS13) — A large outage has thousands of PG&E customers in Sutter and Yuba counties without power Monday morning.

The outage is affecting a total of 15,000 Sutter and 8,500 Yuba residents.

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PG&E says they are working to try and identify what caused the outage and are trying to fix it. The outage is not part of the rolling blackouts that have been prompted by stresses on the power grid.

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Around 3 p.m., County of Sutter Office of Emergency Management is estimating power will be restored to more than 13,000 customers south of Highway 20 around 9 p.m.

In nearby Nevada County, another PG&E outage centered on Penn Valley has 4,300 customers without power. Crews are also investigating what caused this outage.

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Updates to follow.