The incident, reported shortly after 3 am just south of Las Pulgas Road, began when a jeep swerved and struck the guardrail, leaving it disabled in the southbound lanes. Moments later, a Mercedes van collided with the stationary jeep, causing the van to overturn, reported California Highway Patrol Officer Hunter Gerber.

Following this, in a chain reaction, four motorcyclists crashed into the overturned van, resulting in the death of three motorcyclists at the scene.

"Traffic is backed up until Orange County. We are asking everyone to avoid the area if they can," cops urged.

In response to the crash, authorities closed all lanes of southbound I-5, diverting traffic off at Las Pulgas Road and issuing a SigAlert as emergency responders worked diligently to manage the aftermath.

The driver of the Mercedes van sustained life-threatening injuries and was rushed to a hospital for urgent medical treatment.

An investigation into the circumstances surrounding the crash is ongoing.