OCTOBER 1, 2008 — A tractor trailer jackknifed this morning near Encinitas Boulevard on Northbound I-5, causing lane closures and major traffic delays for morning commuters. The accident occurred a few minutes after 8 a.m. The jackknifed truck also involved an accident with two other vehicles, according to the California Highway Patrol. The CHP reported minor injuries and issued a traffic advisory. The advisory was cancelled after 10 a.m.  

Jackknifing, which is fairly rare, can be caused by equipment failure, braking improperly or adverse conditions. Most jackknife accidents happen when a truck is empty.