The US Defense Department says, two Chinese fighter jets carried out an unprofessional intercept of a US surveillance aircraft over the South China Sea. The department says, the incident involved a Navy P3C surveillance aircraft operating in international airspace and two Chinese J-10 fighter jets.<br/><br/>It was the second time in a week that the US has complained about unsafe Chinese operations. Last week, two Chinese fighter planes intercepted a US aircraft in international airspace over the East China Sea.<br/><br/>The Pentagon says the US is reviewing the latest incident and will convey again concerns to the Chinese. A US Navy warship conducted a freedom of navigation operation in China-claimed waters in the region on Wednesday.