On Thursday, an American research ship was retrieving two underwater drones in the South China Sea when a Chinese warship swooped in and stole one of them, Reuters reports.
According to CNN, the Chinese warship was following the USNS Bowditch off the coast of Subic Bay to ensure that it wasn't spying. When the American crew began pulling both of the unmanned, underwater vehicles (UUV) from the ocean—reportedly there to measure oceanic activity—a crew from the Chinese ship came up on a smaller boat and took one of the drones in front of the US crew.
"The UUV was lawfully conducting a military survey in the waters of the South China Sea," a US defense official told Reuters. "It's a sovereign immune vessel, clearly marked in English not to be removed from the water—that it was US property."
The alarming move raises tensions in the South China Sea, where China stakes claim over a string of islands where it has a bunch of weapons and a ramped-up military presence—a point of contention with neighboring Japan, Vietnam, and the Philippines. It also comes in the wake of Donald Trump's post-election victory call to Taiwan, which angered China and violated the US's "One China policy."
Earlier this week, Admiral Harry Harris, the head of US Pacific Command, said the Navy was ready to act should China get aggressive in the region.
"We will not allow a shared domain to be closed down unilaterally no matter how many bases are built on artificial features in the South China Sea," Harris said in Australia on Wednesday. "We will cooperate when we can but we will be ready to confront when we must."
Photo of the USNS Bowditch near Fort Washington, Maryland via the National Museum of the US Navy Flickr account