Senior NATO officials said that since the Chinese vessel surfaced in the middle of the recent military exercise, U.S. Navy officials have been shocked by the advanced technology used by their Chinese counterparts, The Daily Mail said Saturday.

One official said that based on the ease at which the submarine avoided 12 U.S. warships to surface near a 1,000-foot carrier, Navy officials are reconsidering the potential dangers posed by Chinese subs.

While Chinese officials have said the entire incident was a simple coincidence, some U.S. diplomats have accused the vessel of "shadowing" the U.S. fleet during the exercise.

One former member of the British Royal Navy told the newspaper that such allegations could potentially be close to the truth.

"It would tie in with what we see the Chinese trying to do," Commodore Stephen Saunders said, "which appears to be to deter the Americans from interfering or operating in their backyard, particularly in relation to Taiwan."