Pakistan on Thursday commissioned the first of eight Hangor-class submarine in China, a key step in its naval modernization as it expands its defense cooperation with Beijing , the military said. The commissioning ceremony was held in the southern Chinese port city of Sanya, where Pakistani President Asif Ali Zardari was the chief guest. Pakistan's navy chief Adm. Naveed Ashraf and senior military officials from both countries were also present. Zardari and other Pakistani officials have visited China many times in recent years. Zardari, on an official visit to China, said that the induction of the advanced submarine was a “historic milestone” for the navy, reflecting Islamabad’s resolve to maintain a credible and balanced defense posture. He said Pakistan is capable of defending its sovereignty, protect maritime interests and secure key economic lifelines. The Hangor-class submarine is widely believed to be based on China’s Type 039A design.…