UPDATED: Power Outage Puts Thousands in Dark, Prompts Cancelation of ABC Adult School Classes

Updated at 1:20 a.m. Friday: SCE says power will now be restored by 7 a.m. Friday.

A major power outage along the Cerritos-Artesia border that initially affected nearly 2,000 customers has forced the cancelation of Thursday night classes at the ABC Adult School 's Cuesta Drive site.

The Southern California Edison outage, which stemmed from a failed underground cable, began at 12:55 p.m. on Oct. 11, affecting 1,910 customers in Cerritos, Artesia and Norwalk, SCE spokeswoman Vanessa McGrady told Patch. 

"Most of that power was restored in increments by 1:25 p.m. and currently only seven customers continue to have power problems," she added. One of the sites that continues to be affected is property located near the ABC Unified School District.

According to ABCUSD executive administrative assistant Maria Machado, the outage affected power at Tracy High School and the adult school.

"Classes have only been canceled at the Cuesta site," Machado said. "Everything should be back to normal by tomorrow."

Power is expected to be restored by 7 a.m. Friday, according to the utility company's website.

McGrady said it is unclear whether the outage was triggered by rainy weather, but said "there has been lots of lightning today that has caused widespread outages."