A Chinese military aircraft crashed in the South China Sea earlier this month, the Taiwanese intelligence agency said Thursday, providing a possible explanation for China’s closure of a part of the Gulf of Tonkin near Hainan island. Chen Ming-tong, director general of the National Security Bureau, told the Parliament’s Foreign and National Defense Committee that the crash prompted the People's Liberation Army (PLA) to set up a navigation exclusion zone in the adjacent waters to carry out search-and-rescue, and also military training. Chen didn’t provide any further details, citing sensitivities surrounding the source. He did however warn that as the…