Roughly 24 hours ago, a Chinese naval ship seized an unmanned ocean glider belonging to the U.S. Navy. The vessel was purportedly testing water conditions in international waters in the South China Sea, reported The Washington Post.

About 500 yards away, the USNS Bowditch, which sent the vessel out, was performing an oceanic survey with a civilian crew, according to a defense official.

“The United States has through their proper diplomatic channels demarched the Chinese, demanding return of our stuff,” the official added.

However, the Chinese ship instead brought the glider aboard and left the area.

We will update this story as more information becomes available.