NEW DELHI — Pakistan has commissioned the first of eight advanced Chinese submarines, marking a significant step in strengthening its maritime capabilities and deepening defense cooperation with its close ally Beijing. A ceremony to commission the attack submarine called Hangor was held in the Chinese city of Sanya on April 30 in the presence of Pakistani President Asif Ali Zardari and navy chief Naveed Ashraf as well as senior Chinese military officials, according to a Pakistani statement.