A truck stopped in Texas on Friday for a Monster Truck festival.
The truck was loaded with thousands of pounds of supplies and the organizers said it was the biggest event of its kind in the world.
A company representative told NBC News the truck was transporting supplies for the International Association of Machinists and Aerospace Workers and the International Brotherhood of Electrical Workers, the union that represents workers at GM plants in Michigan and Tennessee.
The company said the truck had been used to transport about 10,000 pounds of materials for a number of organizations.
It’s unclear whether the trucks are still in operation.
A spokesperson for the United Automobile Workers, which represents some of the world’s biggest truckmakers, said it’s too soon to say if the truck is still in service.
We don’t know how many people are actually on the truck or if it’s running, she said.
The United States is home to about 20 percent of the global production of high-end trucks, according to the trade group.
The National Transportation Safety Board has said a trucker who goes into a fatal crash and remains on the scene could face charges.