South Korea and the U.S. mounted combined air drills involving a U.S. B-1B strategic bomber on Sunday, a day after North Korea launched an intercontinental ballistic missile(ICBM) toward the East Sea.

According to the Joint Chiefs of Staff(JCS), the allies staged a combined flight in formation over the Korean Peninsula, with F-35A stealth fighter jets and F-15 jets of the South Korean Air Force joined by U.S. F-16 fighters in escorting the B-1B aircraft entering the South’s air defense identification zone.

Some ten military planes took part in the drills, reportedly passing some southern regions at times on their way from the Yellow Sea to the East Sea.

The JCS said the drills demonstrated the combined defense capabilities and posture through the timely and immediate deployment of the U.S.’ extended deterrence assets to the peninsula, indicating that the latest training is a response to the North’s ICBM provocation the previous day.

On Sunday, Pyongyang confirmed that it fired a Hwasong-15 ICBM in a "sudden launching drill” on Saturday. The North’s official Korean Central News Agency said the missile flew 989 kilometers for four-thousand-15 seconds up to a maximum altitude of five-thousand-768 kilometers before hitting a pre-set area in the open waters of the East Sea.