The U.S. military flew two Air Force B-1B Lancer bombers over the Korean Peninsula in a show of force late on Tuesday amid high tensions over North Korea's nuclear and missile programs, South Korea's military said.

The two B-1B bombers were accompanied by two F-15K fighters from the South Korean military after leaving their base in Guam, the South's Joint Chiefs of Staff said in a news release on

Wednesday.

After entering South Korean airspace, the two bombers carried out air-to-ground missile drills in waters off the east coast of South Korea, then flew over the South to waters between it and China to repeat the drill, the release said.

The South Korean military said this was part of a regular exercise to bolster military defences and also to display the alliance between the United States and South Korea.