North Korea fired an alleged ballistic missile on Sunday morning, said South Korean and Japanese military officials said. South Korea’s Joint Chiefs of Staff confirmed to Yonhap that North Korea fired a suspected missile toward the sea from its east coast near Sunan, where the isolated, communist regime’s airport is located. The missile fired on Sunday flew to a maximum altitude of around 390 miles and to a range of about 90 miles, the Joint Chiefs of Staff said in a statement. “For other specifics on the missile, the intelligence authorities of South Korea and the United States are conducting a detailed analysis,” the defense agency said in a statement to reporters. “Our military is tracking and monitoring related [to North Korean] movements and maintaining a readiness posture,” it added. The move was criticized by South Korean and Japanese officials. “There have been frequent launches since the start of the year, …