US Pentagon spokesman Rear Admiral John Kirby described the recent incident on August 19 where a Chinese PLAAF jet came within 20 feet of a US Navy P-8 surveillance aircraft off China's coast near Hainan Island in the South China Sea,  as "very, very close, very dangerous".  US Defence Department and Pentagon officials believe that the Chinese Air Force squadron responsible for the incident is the same unit that has been responsible for the series of incidents this year. They said that a Chinese PLAAF Wing Commander has repeatedly harassed U.S. military aircraft in the South China Sea. In the incident on August 19, the Chinese jet fighter was directed to do a Top Gun-like barrel roll that came "dangerously close" to the US Navy P-8 said to be "on a routine mission". The U.S. Defense Department said that the Chinese J-11 fighter jet flew under the U.S. Navy P-8, with one pass coming within 50 feet of the U.S. plane. On another pass a minute or so later, the Chinese pilot flew directly under and then alongside the P-8, "bringing their wingtips to within 20 feet, and then, before he stabilized his fighter, he conducted a roll over the P-8, passing within 45 feet."