India is concerned about reports of a renewed Pakistani effort to buy F-16 fighter jets from the United States, saying the advanced aircraft could spark an arms race in South Asia even though Washington maintains that no such sales are being contemplated. "We are against introducing such advanced weaponry into South Asia," an Indian government official said Tuesday on the condition of anonymity. "They are not useful in the war on terror, and experience has shown that they could be used against India. ... They could spark a buildup or a weapons race in the region." In September, the Pakistani...