Eleven military vessels from China and Russia found operating near the Aleutian Islands last week were met by four U.S. Navy destroyers, Alaska’s two U.S. senators said. 

The two Republican senators, Dan Sullivan and Lisa Murkowski, issued a joint news release Saturday night saying they had been briefed about the operation.

"We have been in close contact with leadership from Alaska Command for several days now and received detailed classified briefings about the foreign vessels," Murkowski said.

"The incursion by 11 Chinese and Russian warships operating together – off the coast of Alaska – is yet another reminder that we have entered a new era of authoritarian aggression led by the dictators in Beijing and Moscow," Sullivan said.

The war in Ukraine and China-Taiwan tensions have strained U.S. relations with the two countries. "This move is highly provocative," Brent Sadler, a retired Navy captain and senior research fellow at the right-leaning Heritage Foundation, told The Wall Street Journal.

Although the senators' statement suggested the vessels were passing through U.S. waters, the Northern Command told the Journal the combined force did not appear to enter U.S. territory. “Air and maritime assets under our commands conducted operations to assure the defense of the United States and Canada. The patrol remained in international waters and was not considered a threat,” the command told the Journal in a statement.

The command did not immediately respond to USA TODAY's request for comment, nor did the State Department. The Chinese and Russian embassies could not be reached either.

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Have other joint exercises taken place in the area?

This is at least the third year in a row that Chinese naval ships have sailed in or near waters off the Aleutian islands in the Bering Sea and North Pacific Ocean. A similar joint exercise took place last year.

In September 2022, the U.S. Coast Guard reported the crew of the cutter Kimball, during a routine patrol in the Bering Sea, encountered a People's Republic of China guided missile cruiser off Alaska’s Kiska Island. The crew later identified two more Chinese naval ships and four Russian naval vessels, including a destroyer. 

At the time, Coast Guard Rear Adm. Nathan Moore said the formation was operating in accordance with international rules and norms but would be met "presence-with-presence to ensure there are no disruptions to U.S. interests in the maritime environment around Alaska."

In September 2021, Coast Guard cutters in the Bering Sea and North Pacific Ocean encountered Chinese ships, some about 50 miles off the Aleutians, according to the Associated Press.

What has been the US response?

Sullivan said he was encouraged by the Navy’s response this year, adding it "sends a strong message to Xi Jinping and Putin that the United States will not hesitate to protect and defend our vital national interests in Alaska."

Last summer's response was "tepid," Sullivan said. He said he had "encouraged senior military leaders to be ready with a much more robust response should such another joint Chinese/Russian naval operation occur off our coast."

The incident is "a stark reminder of Alaska’s proximity to both China and Russia, as well as the essential role our state plays in our national defense and territorial sovereignty," Murkowski said. 

Concerns not new over activity in the Arctic region

The U.S. Navy and others have been concerned for decades about increased military activity in the Arctic region given the warming climate and more open water as a result of melting sea ice.

The incident last summer occurred about a month after NATO had warned about China's interest in the Arctic and Russia's military buildup there. The Associated Press reported that NATO Secretary General Jens Stoltenberg said Russia had set up a new Arctic command and opened new and former Arctic military sites.

Five Chinese naval ships also sailed through U.S. territorial waters off Alaska while participating in a joint exercise with Russia in September 2015.