A U.S. Air Force B-1B Lancer assigned to the 37th Expeditionary Bomb Squadron, takes-off to fly a bilateral mission with Japanese and South Korea Air Force jets in the vicinity of the Sea of Japan, from Andersen Air Force Base, Guam, October 10, 2017. Staff Sgt. Joshua Smoot/U.S. Air Force/Handout via REUTERS

SEOUL (Reuters) - North Korea said U.S. B-1B bombers flew over the Korean Peninsula on Thursday and carried out bombing drills simulating attacks on major targets in the country, the North’s official KCNA news agency said on Friday.

The strategic bombers, escorted by U.S. and South Korean fighter jets, flew from the Anderson Air Force Base in Guam, to conduct a “surprise” strike drill, the KCNA said.

There was no immediate confirmation from the U.S. and South Korean militaries.