North Korea fired an unspecified ballistic missile, the South Korean military reported to North Korea’s Yonhap News Agency on Wednesday (August 30). US National Security Council spokesman John Kirby declined to comment.

The firing comes hours after the US deployed B-1B bombers as part of its annual joint military exercises with South Korea, dubbed “Ulchi Freedom Shield”, which runs until August 31.

Kim Jong-un, the North Korean leader, believes that the joint military exercises carried out in the peninsula by Washington and Seoul pose a threat. He accused the United States of being “more restless than ever” with naval maneuvers and the permanent deployment of strategic nuclear assets in the waters around the Korean peninsula.

Since the start of the year, North Korea has increased its missile tests and has, moreover, attempted twice to deploy a first spy satellite. These attempts ended in failure as the United States, South Korea and Japan have increased their defense cooperation in recent months.