Two B-1B Lancers based in Guam flew a mission in the vicinity of the Sea of Japan late Tuesday, the US Pacific Air Forces said in a statement.
The U.S. military said in a separate statement Japanese fighters had also joined the drill, making it the first night-time combined exercise for the U.S. bombers with fighters from Japan and South Korea.
Last month, South Korea carried out a simulated attack on North Korea's nuclear test site, following joint military drills with the U.S. in late August.
Pyongyang has denied responsibility for the cyberattacks in its state media, criticising Seoul for "fabricating" claims about online attacks.
Vice Foreign Minister Lim Sung-nam will hold strategic talks with visiting U.S. Deputy Secretary of State John Sullivan on October 18 in Seoul, according to Seoul's foreign ministry. Pyongyang belatedly responded by relocating some of its military aircraft to its east coast, the National Intelligence Service then said.
"These B-1 sorties reflect South Korea's demand for more extended deterrence assurances", Pinkston tells VOA.
Outside governments and worldwide human rights organizations say Kim rules as a tyrant over a largely malnourished and abused population while enjoying a luxurious lifestyle backed up by a weapons program almost advanced enough to viably target the US mainland with nuclear-tipped missiles. Kim is the third generation of his family to rule North Korea.
Rhee Cheol-hee, a South Korean lawmaker who sis on its parliamentary defence committee, said 235GB of military documents were swiped from the Defence Integrated Data Centre, adding that 80 per cent of these documents have yet to be identified.
The South's Yonhap news agency quoted Lee as saying that 235 gigabytes of military documents were taken. The US President is expected to send an important message to North Korea.
However, North Korean hackers have been suspected to have previously targeted rival South's power grids with wiper malware.
In retaliation against Seoul's closure of the complex, North Korea kicked out all remaining South Koreans and announced that it would freeze their assets and liquidate them.