One of the J-10s flew underneath the U.S. EP-3 aircraft at a high rate of speed, slowed, and then pulled up, forcing the U.S. plane to "take evasive action to prevent the possibility of collision," Pentagon spokesman Capt. Jeff Davis said.
A U.S. official said the Chinese jet's actions were described as "unsafe."
Davis said Sunday's interaction, which happened late morning local time, was "uncharacteristic" of typical Chinese military behavior.
"There are intercepts that occur in international airspace regularly, and the vast majority of them are conducted in a safe manner," he said. "This was the exception, not the norm."
Davis said the J-10s and EP-3 were flying "wing to wing" as well, but didn't know if they did so before or after the intercept.