Beijing — China verbally protested the alleged incursion of a U.S. Air Force U-2 spy plane into a no-fly zone imposed during live-fire military exercises in the country's north on Wednesday. Beijing test fired four missiles as an apparent warning to the U.S. military in response, including one described by the South China Morning Post newspaper as an "aircraft carrier-killer."
In a statement issued late Tuesday, the Ministry of National Defense said the alleged U-2 flight had "seriously interfered in normal exercise activities" and "severely incurred the risk of misjudgement and even of bringing about an unintended air-sea incident."
"This was a naked act of provocation," the ministry said, quoting spokesperson Wu Qian. China has lodged a stern protest and demanded the U.S. cease such actions, Wu said.
The statement did not give details on the time and place of the drills, but the information matched exercises the Maritime Safety Administration said started Monday and would run through Sept. 30 over the Bohai Gulf east of Beijing.
Chinese officials did not mention the test firing of missiles on Wednesday, but a U.S. defense official confirmed to CBS News national security correspondent David Martin the report by the Hong Kong-based South China Morning Post that at least two ballistic missiles had been launched.
On Thursday, a U.S. defense official told CBS News that China's military had in fact launched four medium-range missiles from the country's mainland, all of which splashed down in the South China Sea. The official said the launch appeared to have been part of the previously announced military exercise.
In its report Wednesday, the South China Morning Post said one of the missiles fired was a DF-21d, which it said has been described by Chinese state media as the "world's first anti-ship ballistic missile."
Relations between the U.S. andhave sunk to amid disputes over myriad issues including trade, technology, Taiwan and the South China Sea.
The high-altitude U-2 reconnaissance planes were flown over China, the former Soviet Union and other countries in the Communist bloc during the Cold War and upgraded versions continue to support U.S. missions.
China is also holding naval drills in the South China Sea, which it claims virtually in its entirety but over which five other governments also exercise claims. China objects to all U.S. military activity in and over the strategic waterway, especially "" during which U.S. Navy ships sail near to Chinese-held islands.
Another naval exercise is planned from Thursday to Sunday in the East China Sea despite warnings issued over Typhoon Bavi, which is affecting the Korean Peninsula.
The defense ministry earlier this month said combat exercises were held in the Taiwan Strait and surrounding waters that were a "necessary move responding to the current security situation in the Taiwan Strait and were meant to safeguard national sovereignty."
Chinaand threatens to use military force to bring under its control the island that is a self-governing democracy and close U.S. ally.
Washington and Taipei havein recent years and this month, Health and Human Services Secretary Alex Azar became the , prompting a Chinese protest.
The eastern command of the People's Liberation Army will "stay on high alert and take all necessary measures to fight against provocations and protect national sovereignty and territorial integrity," the ministry quoted command spokesperson, Senior Col. Zhang Chunhui, as saying.