The U.S. Air Force sent two B-1B strategic bombers stationed on Guam on a wide-ranging flight for joint drills with the Air Self-Defense Force and South Korea's military Tuesday, just hours after the death of a former U.S. detainee in North Korea was announced.

The 10-hour mission from Guam's Andersen Air Force Base saw the B-1Bs take to the skies near Kyushu and above the East China Sea before departing for the Korean Peninsula, the U.S. Pacific Air Forces said in a statement.

The separate bilateral exercises, in which U.S. bombers linked up with ASDF F-15s and Republic of Korea Air Force F-15s, were the latest in an unprecedented string of drills between the U.S. allies after a spate of North Korean missile launches and the death of onetime detainee Otto Warmbier.