A Chinese attack submarine conducted a simulated cruise missile attack on the aircraft carrier USS Reagan during a close encounter several weeks ago, according to American defense officials.

The targeting incident near the Sea of Japan in October violated China’s 2014 commitment to the multinational Code for Unplanned Encounters at Sea, known as CUES, designed to reduce the risk of a shooting incident between naval vessels, said officials familiar with details of the encounter they described as "serious."

A section of the non-binding 2014 agreement states that commanders at sea should avoid actions that could lead to accidents or mishaps. Among the actions to be avoided are "simulation of attacks by aiming guns, missiles, fire control radar, torpedo tubes or other weapons in the direction of vessels or aircraft encountered."

Navy officials recently briefed congressional staff on the incident that took place during the weekend of Oct. 24—days before the Navy warship USS Lassens sailed within 12 miles of disputed Chinese islands in the South China Sea, triggering vocal criticism from Beijing.

The Obama administration has kept details of the submarine targeting incident secret to avoid upsetting military relations between the Pentagon and the People’s Liberation Army.

Asked directly about the incident, Adm. Harry Harris, commander of the U.S. Pacific Command, did not deny that the encounter occurred. "I have nothing for you," Harris stated in an email.

Pacific Command spokesman Capt. Darryn James earlier directed questions about the targeting to the Chinese navy. James also stated that Navy ships in the region are capable of defending themselves.

"I cannot discuss submarine operations, reports of submarine operations, or rumors of submarine operations," James said. "I can tell you that we are completely confident in the effectiveness and capabilities of the ships and aircraft of the forward-deployed naval force."

Additional details about the submarine-carrier encounter emerged after the Free Beacon first reported the incident Nov. 3.

The nuclear-powered Reagan is currently the Navy’s sole forward-deployed aircraft carrier strike group. It arrived at its base in Yokosuka, Japan on Oct. 1 and replaced the USS Washington strike group there.

Aircraft carrier strike groups are equipped with anti-submarine warfare capabilities, including ships armed with sensors and submarine-killing torpedoes.

Disclosure of the aircraft carrier targeting comes as two Chinese navy warships arrived in Pearl Harbor on Sunday.

China’s official news agency said the ships’ visit to Hawaii will last five days. "During the fleet's stay here, the U.S. navy and the Chinese fleet will hold receptions for each other," Xinhua said. "Friendly sports activities, such as basketball and soccer games, will be held between the two sides."

The Pentagon has made developing closer ties with the Chinese military a top priority, despite concerns that the exchanges are boosting Chinese war-fighting capabilities.

Members of Congress have called for curbing the exchanges in the face of Chinese cyber attacks and destabilizing activities in the South China Sea.

On Capitol Hill, Rep. Randy Forbes (R., Va.), chairman of the House Armed Services subcommittee on sea power, said he is concerned by reports of China’s simulated ship attack.

"If true, this would be yet another case of China trying to show us that they can hold our forces in the region at risk," said Forbes.

"Coming on the heels of anti-satellite tests and other demonstrations, this latest incident should be a reminder of the destabilizing course that China is on and the challenges we face in maintaining a stable military balance in the Asia-Pacific region," Forbes added.

Naval warfare analysts said the incident highlights Chinese efforts to counter U.S. aircraft carrier strike groups, the United States’ major power projection capability in the Pacific.

Retired Navy Capt. Jim Fanell, a former Pacific Fleet intelligence chief, said the submarine incident, if confirmed, would be another clear case of the Chinese navy targeting the carrier strike groups, known as CVNs.

"The PLAN submarine force is on the leading edge of the PLAN for targeting U.S. CVNs in the East Asia arena, all for the expressed purpose of being able to attack and disable them in a contingency operation" he said. PLAN stands for People’s Liberation Army Navy.

Rick Fisher, a China military specialist at the International Assessment and Strategy Center, said the Chinese navy operates several types of submarines capable of firing anti-ship cruise missiles.

The Song-class and Yuan-class attack submarines can fire two types of torpedo tube-launched anti-ship cruise missiles, including the YJ-82 with a range of up to 22 miles.

Eight of China’s 12 Russian-made Kilo-class submarines are armed with Club anti-ship missiles with a range of up to 137 miles. Newer Shang-class submarine can also fire cruise missiles.

"That the U.S. side would be able to determine that the submarine was conducting a cruise missile strike would indicate that the Chinese submarine was under close surveillance," Fisher said.

"That also raises the potential that the U.S. side could determine the Chinese submarine had hostile intent, potentially leading to the launching of defensive weapons."

Fisher said the incident was serious because a U.S.-China shootout would likely result in the destruction of the Chinese submarine and the loss of its crew. "Even though China would have been at fault for the incident, the Chinese government would likely then use it as an excuse for initiating a series of attacks or incidents against U.S. naval forces," he said.

Additionally, the targeting "certainly runs counter to a 2014 U.S.-China agreement to avoid such incidents at sea, which could indicate that China may have little intention to honor such this or other military confidence building agreements," Fisher said.

The Navy’s main close-in anti-submarine warfare weapon is the RUM-139C rocket-launched anti-submarine torpedo, with a range of about 17 miles.

Ben Ho Wan Beng, a military analyst at Singapore’s S. Rajaratnam School of International Studies, said the Chinese military is focused on using of cruise missiles against carriers. "China seems to stress the centrality of this weapon in attacking ships," he wrote last week in the Diplomat.

Recent improvements in Navy defenses against submarines include a new electronic combat system, a towed sensor array, and the P-8 maritime submarine patrol aircraft.

"Whether or not these and similar measures would enable the U.S. to retain a distinctive edge in the undersea combat realm vis-à-vis China remains to be seen," Ho said.

Lyle J. Goldstein, a U.S. Naval War College expert on the Chinese military, wrote on Sunday that a Chinese defense journal recently discussed ways to sink U.S. aircraft carriers.

A Chinese military analyst recently revealed that China is closely studying a report from earlier this year revealing that a small nuclear-powered French submarine successfully conducted a simulated attack on the aircraft carrier USS Roosevelt, sinking the ship and several support ships in the simulation.

"The article illustrates how Chinese military analysts are diligently probing for cracks in the U.S. Navy’s armor," Goldstein wrote in the National Interest.

The October showdown between the Chinese submarine and the Reagan took place as the carrier sailed around the southern end of Japan on the way exercises in the Sea of Japan along with four other strike group warships.

Days after the incident, two Russian strategic bombers flew within a mile of the carrier at a height of 500 feet, prompting F-18s from the ship to scramble and intercept them.

The October incident was not the first time a Chinese submarine threatened a U.S. carrier strike group.

In 2006, a Song-class attack submarine surfaced undetected within torpedo range of the USS Kitty Hawk.

The state-controlled China Daily praised the implementation of the CUES maritime code agreement last year as a major step in U.S.-China military relations.

Wen Bing, a researcher at the Chinese army’s Academy of Military Sciences, told the newspaper that the code of conduct and U.S.-China warship exercise at the time "demonstrate the resolve of both countries to deepen military ties and avoid a maritime conflict escalating due to a lack of communication."

In December 2013, a Chinese amphibious warship sailed in front of the guided missile cruiser USS Cowpens and stopped, causing a near collision in the South China Sea.

A Chinese Embassy spokesman did not respond to an email request for comment.