The mystery of China’s levitating cars has been solved — and the explanation is very down-to-Earth.

Viral video appears to show three vehicles suddenly going airborne as they approach an intersection in the city of Xingtai, about 250 miles south of Beijing.

“I was driving slowly straight ahead,” a van driver told CCTV. “All of a sudden, I was lifted up. The street cleaner car snagged on the wire. The wire just so happened to be underneath our car and it sent us flying.”

Turns out that misplaced cables got caught in a street sweeper’s spinning brooms, acting as a tripwire that triggered the gravity-defying incident, according to the blog Shanghaiist.