UPDATE 12/17 1:40 p.m. EST:China said Saturday that its military seized a U.S. Navy unmanned underwater glider in the South China Sea to ensure the "safe navigation of passing ships," in one of the most serious incidents between the two militaries in years.
The Chinese navy on Thursday seized the drone, which the Pentagon said was being operated by civilian contractors to conduct oceanic research.
(The Associated Press contributed to this report)
A Chinese naval vessel stole a U.S. underwater research drone in the South China Sea on Thursday while a U.S. crew was watching, reports Fox News.
The Chinese ship that grabbed the drone had been shadowing USNS Bowditch, the American vessel that deployed the drone, for days.
The crew of the Bowditch watched as the the Chinese naval ship, only a quarter of a mile away, took the drone.
Chinese ships have regularly shadowed U.S. vessels over the past few months. China has also been building islands and reportedly storing weapons in the disputed territory.
"We call upon China to return our [unmanned underwater vehicle] immediately, and to comply with all of its obligations under international law," Pentagon Press Secretary Peter Cook said.
The drone was used to map the ocean floor and collect environmental data and did not contain any classified material.
The Pentagon released this statement online.
If you don't think China seizing a US Navy drone is a retaliation for Trump's call with Taiwan, you aren't paying attention.— Simar (@sahluwal) December 16, 2016
Some on Twitter think that the theft could be politically motivated.
WATCH | How underwater drones gather data at sea
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