A driver illegally passing another vehicle on a Lake County highway Friday triggered a three‑car collision, killing a Lakeport woman, according to the CHP.

Lee Ann Nelson, 57, died in the 4:50 p.m. crash on Highway 20 near Upper Lake. Her name was released Monday afternoon by the Lake County Coroner’s Office.

CHP Officer Kory Reynolds said David Ostberg, 47, of Kelseyville, in a 2013 Honda Accord was illegally passing a large truck on the two‑lane rural highway when he moved into the path of an oncoming 2017 Cadillac CTS. The Honda sideswiped the Cadillac and went into a spin, hitting the 2008 Kia Rio driven by Nelson broadside.

Ostberg had minor injuries. Cadillac driver Matthew Hansen, 32, of Witter Springs, was not injured.

CHP investigators Monday still were looking into the crash, which could result in a manslaughter charge. Alcohol, drugs and speed weren’t believed to be factors.

You can reach Staff Writer Randi Rossmann at 707‑521-5412 or randi.rossmann@pressdemocrat.com. On Twitter@rossmannreport.