Here is another link
http://www.sigalert.com/map.asp?Region=Los+Angeles The trucks on the Harbor Freeway were pulled over, at least the first 2 and the rest kept going. I think if they didn't have a sign on their truck protesting the CHP didn't know who was involved and who was stuck in traffic with them.
The drivers in the first incident on the I-5 had people pick them up and they left their trucks on the freeway. Seems like an expensive protest to me, towing, impound fees etc. That would pay for a lot of diesel fuel. And the people paying for it are the commuters stuck behind this mess, their gas is expensive too.