While the US and Russia have offered different accounts of Friday’s incident, all indications suggest it took place in waters off the coast of China.

That is uncommon, according to Carl Schuster, a retired US Navy captain and former director of operations at the US Pacific Command’s Joint Intelligence Center.

“The Russians normally harass our ships when they are operating in waters the Russian consider to be within their sphere of Influence (Black Sea, Barents Sea and the waters off Vladivostok),” said Schuster, who spent 12 years at sea on US warships…

“It seems as if they’re working in concert with the Chinese. They’re looking at the kinds of things that they can, that they can do in concert with the Chinese to challenge the US. And if it means helping the Chinese out in the Pacific, they will do so,” according to retired Air Force Col. and CNN military analyst Cedric Leighton.