The United States deployed a massive B-52 bomber plane on a low-level flight over its ally South Korea on Sunday, a show of force following North Korea's nuclear test last week.
The B-52 Stratofortress is a long-range bomber capable of carrying nuclear weapons. The plane was spotted cruising low above Osan Air Base about 40 miles south of Seoul on Sunday afternoon. It was flanked by two fighters, a US F-16 and a South Korean F-15, before returning to its base on the Pacific island of Guam, the US military said in a statement. The flight was "in response to recent provocative action by North Korea," the statement said.
"The United States remains steadfast in its commitment to the defense of the Republic of Korea (South Korea) and to maintaining stability on the Korean Peninsula, to include extended deterrence provided by our conventional forces and our nuclear umbrella," said US Lieutenant General Terrence O'Shaughnessy.
North Korean leader Kim Jong-un has maintained that Wednesday's test was of a hydrogen bomb and said it was a self-defensive step against a US threat of nuclear war. The country's fourth nuclear test angered both China, its main ally, and the United States, although the US government and weapons experts doubt the North's claim that the device was a full-fledged hydrogen bomb. Some experts have suggested it was perhaps a boosted fission weapon, which more complex than a conventional atomic bomb but less powerful than a thermonuclear device.
After the North's last test, in 2013, the United States sent a pair of nuclear-capable B-2 stealth bombers over South Korea. At the time, the North responded by threatening a nuclear attack on the United States.
The United States is also considering sending a nuclear-powered aircraft carrier to waters off the Korean peninsula next month to join a naval exercise with Seoul, South Korea's Yonhap news agency reported without identifying a source. US officials said they had no knowledge of the plan.
The two Koreas are still technically in a state of war after their 1950-53 conflict — in which the US supported South Korea — ended in a truce, not a peace treaty. The US has about 28,500 troops based in South Korea.
An editorial in the North's Rodong Sinmun newspaper on Sunday called for a peace treaty with the US, which is the North's long-standing position. "Only when a peace treaty is concluded between the DPRK (North Korea) and the US can genuine peace settle in the Korean Peninsula," North Korean state news agency KCNA quoted the editorial as saying.
The United States and China have both dangled the prospect of better relations, including the lifting of sanctions, if North Korea gives up its nuclear weapons.
Earlier on Sunday, KCNA quoted Kim as saying no one had the right to criticize the North's nuclear tests.
"The DPRK's H-bomb test … is a self-defensive step for reliably defending the peace on the Korean Peninsula and the regional security from the danger of nuclear war caused by the U.S.-led imperialists," it quoted Kim as saying.
"It is the legitimate right of a sovereign state and a fair action that nobody can criticize," he added.
Kim's comments were in line with the North's official rhetoric blaming the United States for deploying nuclear weapons on the Korean peninsula to justify its nuclear program but were the first by its leader since Wednesday's blast. The United States has said it has no nuclear weapons stationed in South Korea.
Kim noted the test was being held ahead of a rare congress of its ruling Workers' Party later this year. The test was also conducted two days before Kim's birthday on January, when he is believed to have turned 33.
South Korea continued to conduct high-decibel propaganda broadcasts across the border into the North on Sunday. The broadcasts, which include K-pop music and statements critical of the Kim regime, began on Friday and are considered an insult by Pyongyang. A top North Korean official told a rally on Friday that the broadcasts had pushed the rival Koreas to the "brink of war."
Daily life was mostly as normal on the South Korean side of the border on Sunday. A popular ice fishing festival near the border attracted an estimated 121,300 people on Saturday and another 100,000 on Sunday, Yonhap reported.
On Friday, in celebration of the purported H-bomb test and Kim's birthday, North Korea held a massive rally in Pyongyang that included fireworks and choreographed dancing.
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