SANTA MARIA, Calif. — Crews have restored power to most of the 145,000 Pacific Gas and Electric Co. customers hit by a weekend outage that darkened a large part of California's Central Coast.

An outage map on the company's website shows just one customer in Santa Maria remains without electricity early Monday morning.

Santa Maria, which has about 100,000 residents, was the largest city affected by the Sunday night outage that stretched from the beach town of Cambria in San Luis Obispo county to Solvang in Santa Barbara's wine country.

PG&E tweeted that equipment failure at a substation caused the outage.

No major problems were reported, although one hospital canceled a surgery.

THIS IS A BREAKING NEWS UPDATE. Check back soon for further information. AP's earlier story is below.

A widespread power outage darkened a swath of California's Central Coast, affecting approximately 145,000 Pacific Gas and Electric Company customers late Sunday, the utility said.

The outage stretched from the beach town of Cambria in San Luis Obispo county to Solvang in Santa Barbara's wine country.

Santa Maria, with a population of about 100,000, was the largest city affected by the outage.

"At first we thought it was a brown out, with half of the city lights out about 9:15 p.m.," the city's police Chief Ralph Martin said. "But 10, 15 minutes later the whole city was without power."

Martin said the outage forced the police department to switch to generator power.

Extra officers were called to patrol the streets, direct traffic and respond to several reports of vandalism at local businesses, he said.

PG&E tweeted that equipment failure at a substation caused the outage, and that crews restored power to about 90,000 customers around midnight.