Alaska lawmakers voiced concerns after the U.S. military announced it had intercepted Russian and Chinese fighter jets roughly 200 miles off the coast of Alaska on Wednesday.

The activity was “not seen as a threat,” North American Aerospace Defense Command (better known as NORAD) said in a statement, promising to “monitor competitor activity near North America and meet presence with presence.”

However, the news prompted Sen. Dan Sullivan, R-Alaska., a member of the Senate Armed Services Committee, to call for more military resources in the area.

“As I have been warning our Pentagon leaders for years, these kinds of joint Russia and China incursions on the sea and in the air near Alaska will continue,” Sullivan said in a statement. “For that reason, the United States needs to continue to build up our military forces and the infrastructure that goes with it in Alaska to protect our nation’s vital interests in the Arctic and the INDOPACOM theater,” he said, referring to U.S. Indo-Pacific Command.

And Sen. Lisa Murkowski, R-Alaska., wrote in a post on X that Wednesday’s “unprecedented provocation” shows why the Air Force should not shut down the 611th Air Operations Center or reduce the Alaska Air National Guard.

Sullivan and Murkowski were similarly frustrated after a Chinese spy balloon traversed their state before crossing the continental U.S. in February 2023.

“As an Alaskan, I am so angry,” Murkowski said during a Senate Appropriations Committee hearing last year. “I want to use other words, but I’m not going to. The fact of the matter is Alaska is the first line of defense for America.”

Wednesday’s incursion, which took place outside U.S. sovereign airspace, marked the first time Russia and China have teamed up to send a joint bomber task force into the Alaska Air Defense Identification Zone. The ADIZ is just outside sovereign airspace and, according to NORAD, is “a defined stretch of international airspace that requires the ready identification of all aircraft in the interest of national security.”

It comes as defense officials and lawmakers increasingly worry about cooperation between the two adversaries.

“This is the first time that we’ve seen these two countries fly together like that,” Defense Secretary Lloyd J. Austin III told reporters during a press conference on Thursday. “And if it happens again, if there’s any kind of challenge from any direction, I have every confidence that NORTHCOM and NORAD will be at the ready and will be able to intercept.”

Austin said the Pentagon’s primary concern about Russia-China cooperation is the possibility of China aiding Russia’s war against Ukraine. NATO leaders earlier this month called China a “decisive enabler” of the war, a notable accusation from an alliance that has grown increasingly unified against Beijing.

“We’re concerned about China providing support to Russia’s illegal and unnecessary war in Ukraine, and we’ve seen evidence of that,” Austin said. “And we would hope that that would cease going forward, but, but again, we’ll see.”

The issue has attracted lawmaker attention, too. The Senate Armed Services Committee wants a new Pentagon strategy for dealing with the looming prospect of two “near peer” nuclear powers, both Russia and China, and for potentially handling “simultaneous aggression” by those two countries against the United States or its allies.

The requirement for the classified U.S. strategy review is included inside the Senate’s $908.4 billion fiscal 2025 NDAA, which the chamber may vote on in the coming weeks.

The Senate bill would also demand a separate report from the Defense Department on the extent of military cooperation between China and Russia.