SEATTLE – Authorities in Seattle temporarily closed a street after motorists were stunned by dozens of large metal balls that spilled out of a truck and cascaded down the street, damaging several cars.

A video taken by a person at the scene Wednesday afternoon shows the balls loudly bouncing and rolling down the street as a driver slowly backs up, apparently attempting to escape the onslaught.

A Seattle police spokesman said the balls appeared to be “really big ball bearings” and that it was unclear what caused the load of them to fall out of the truck.