While sign spinning today

While sign spinning today at Cerrillos and Rodeo in Santa Fe, I looked when I heard clackey-clackety. The back left wheel was coming away from a pickup truck across 6-lane Cerrillos from me. The wheel wobbled and got further and further from the truck.The driver had just time to pull into the lot of a propane gas business before the wheel and the axle shaft came off and rolled a ways before falling and stopping.