Fighter jets buzzed the skies and submarines cruised underwater Sunday as a flotilla of U.S. and South Korean warships led by a nuclear-powered U.S. supercarrier began exercises that have enraged North Korea.
U.S. officials denied North Korea's claims the maneuvers off Korea's east coast were a provocation, but said they were meant to send a strong message over the sinking of a South Korean warship in March that left 46 sailors dead.
The drills, set to run through Wednesday, involve about 8,000 U.S. and South Korean troops, 20 ships and submarines and 200 aircraft. The USS George Washington, with several thousand sailors and dozens of fighter jets aboard, was deployed from Japan.
"We are showing our resolve," said Capt. David Lausman, the carrier's commanding officer.
The exercises will be the first in a series of U.S.-South Korean maneuvers conducted in the East Sea off Korea and in the Yellow Sea closer to China's shores in international waters.
The exercises also are the first to employ the F-22 stealth fighter — which can evade North Korean air defenses — in South Korea.
North Korea has called the drills an "unpardonable provocation" and threatened to retaliate with "nuclear deterrence" and "sacred war."
The North routinely threatens attacks whenever South Korea and the U.S. hold joint military drills, which Pyongyang sees as a rehearsal for an invasion. The U.S. keeps 28,500 troops in South Korea and another 50,000 in Japan, but says it has no intention of invading the North.
Still, the North's latest rhetoric carries extra weight following the sinking of the Cheonan warship in late March.
Rear Adm. Daniel Cloyd, the top U.S. official in the exercise, said he was confident the United States could respond to any threat. He said no significant action by the North's military had been observed.
"We are monitoring the region all the time and we are very confident we can respond to any situation," he said.
Washington and Seoul blame Pyongyang for the sinking of the 1,200-ton Cheonan warship near the Koreas' maritime border. A five-nation team of investigators concluded a North Korean torpedo sank the Cheonan, considered the worst military attack on the South since the 1950-53 Korean War.
North Korea, which denies any involvement in the sinking, has warned the United States against attempting to punish it.
"Our military and people will squarely respond to the nuclear war preparation by the American imperialists and the South Korean puppet regime with our powerful nuclear deterrent," the North's government-run Minju Joson newspaper said in a commentary headlined, "We also have nuclear weapons."
The commentary was carried by the official Korean Central News Agency.
The North's powerful National Defense Commission issued a similar threat Saturday, saying the country "will start a retaliatory sacred war."
Pyongyang's rhetoric was seen by most as bluster, but its angry response to the maneuvers underscores the rising tension in the region.
Capt. Ross Myers, the commander of the George Washington's air wing, said the exercises were not intended to raise tensions.
But the George Washington, one of the biggest ships in the U.S. Navy, is a potent symbol of American military power, with about 5,000 sailors and aviators and the capacity to carry up to 70 planes.
"North Korea may contend that it is a provocation, but I would say the opposite," Myers said. "It is a provocation to those who don't want peace and stability. North Korea doesn't want this. They know that one of South Korea's strengths is its alliance with the United States."
Myers said North Korea's threats to retaliate are being taken seriously, however.
"There is a lot they can do," he said. "They have ships, they have subs, they have airplanes. They are a credible threat."
The maneuvers underscore a diplomatic blitz by the United States aimed at further tightening the screws on North Korea.
U.S. Secretary of State Hillary Rodham Clinton announced Wednesday, after visiting the Demilitarized Zone dividing the two Koreas, that the U.S. would slap new sanctions on the North to stifle its nuclear ambitions and punish it for the Cheonan sinking.
The European Union is also considering new sanctions on North Korea.
The deployment of the supercarrier to the area off Korea was also raising eyebrows in China — which was believed to have been concerned about having the carrier operate too close to its own shores.
In what has been seen as a bow to Chinese sensitivities, the George Washington will not be joining the maneuvers later this summer in the Yellow Sea.
But Cloyd, the top U.S. official in the exercise, said the carrier may be back.
"We reserve the right to exercise in international waters anywhere in the world," he said.
The Nimitz-class carrier had been expected to join in exercises — code-named "Invincible Spirit" — off South Korea sooner, but the Navy delayed those plans as the United Nations Security Council met to deliberate what action it should take over the Cheonan sinking.
The council eventually condemned the incident, but stopped short of naming North Korea as the perpetrator.
In Seoul, meanwhile, about 150 anti-war activists rallied Sunday near the U.S. Embassy, chanting slogans such as "We are opposing the drills!" and "Scrap the South Korean-U.S. alliance!" The activists said the training would only deepen tension in the region. The rally was peaceful and there was no reports of clashes with riot police.
Associated Press writer Hyung-jin Kim and AP photographer Young-joon Ahn in Seoul contributed to this report.
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