KANSAS CITY, Mo. — Semitrailers hauled two massive SpaceX tanks moved through the Kansas City metro Tuesday afternoon, causing long backups on local highways.

The company hired to haul the tanks confirmed to FOX4 they are empty and belong to SpaceX, tech billionaire Elon Musk’s space exploration company.

A representative for the company said they are taking hte tanks to a SpaceX facility in Texas.

The Missouri State Highway Patrol escorted the haulers along Missouri Highway 210 before heading west on Interstate 70 and then north on Interstate 435, apparently to avoid downtown Kansas City.

At multiples times, officers stopped all traffic in both directions to allow one hauler to cross a bridge. The haulers crossed one at a time, likely because of the weight of the tanks they transported.

The semis continued on westbound I-435 toward Kansas City International Airport then southbound on the interstate toward Kansas City, Kansas.

FOX4 is working to confirm more details. We’ll update this story as we learn more.