Black SUVs spotted on hwy 1 aug 21

3 black suburbans in a row (with an odd yellow bar hitch sticking out the back), entered hwy 1 east at Hastings with their flashers and skirted thru traffic, then turned them off and got caught in traffic like the rest of us cattle.

There were uniformed people (police I'm guessing) inside.

Anybody know what the yellow bar in the back is for? Or who they are? Some sort of government escort I'm guessing...