SAN DIEGO (CBS 8) - A chain reaction crash on Interstate 5 sends four people to the hospital.

Two cars crashed into one another and were stopped in the number one lane at the Clairemont Drive exit around 8:15 p.m. Wednesday. Then three cars crashed trying to avoid the first accident. A total of five cars were involved.

"This was not an extraction situation, this was not a rescue. It was just a multiple patient situation. Just assessing, mostly c-spining patients, getting them onto the gurney, then getting them off ambulances to the emergency departments,” explained Battalion Chief John Strock with San Diego Fire-Rescue.

The accident backed up traffic for miles and prompted a SigAlert.

According to the California Highway Patrol, none of the injuries were considered life-threatening.