US Security Chief Says One Suspected Terrorist Is Arrested at Canadian Border ‘Almost Weekly’

Homeland Security Secretary Markwayne Mullin says ‘fracturing’ relationship between the two countries need to be fixed to ensure security.

U.S. Homeland Security Secretary Markwayne Mullin testifies before the U.S. House Committee on Homeland Security in Washington on June 3, 2026. AP Photo/Cliff Owen

U.S. Homeland Security Secretary Markwayne Mullin says American authorities apprehend a suspected or wanted terrorist at the Canada-U.S. border “almost weekly,” while warning that “fracturing” relations between the two countries could leave both more vulnerable to criminal organizations, fentanyl traffickers, and other threats.

Mullin made the remarks June 17 during a fireside conversation with Canada’s Public Safety Minister Gary Anandasangaree at the Center for Strategic and International Studies in Washington. He added that the United States is concerned that many criminal organizations whose activity has been reduced due to enforcement at the U.S.-Mexico border are moving operations to the northern border.

“We arrest a terrorist—one either on the watch list or wanted terrorist—on our northern border almost weekly,” Mullin said. “Some of the fracturing we have right now between the countries, we’ve got to figure it out.”

Mullin was sworn in as secretary of the Department of Homeland Security on March 24, succeeding Kristi Noem after she was reposted as the special envoy for the Shield of the Americas by U.S. President Donald Trump.

‘Solid Foundation’

Mullin said improving Canada-U.S. relations and building a “solid foundation” is vital to ensuring that criminals don’t take advantage of a U.S.-Canada rupture in relations.

“We’ve got to move past our differences so we can build that solid foundation, because we have criminals, we have cartels, we have organized crime that’s taken advantage of it,” he added.

While Mullin warned that criminal organizations along with terror suspects and illegal immigrants are increasingly targeting the U.S. northern border, Anandasangaree said Canada has already made considerable progress in tightening border security. Illegal migration from Canada into the United States has declined by 99 percent since Ottawa introduced a plan to boost border security in December 2024, the minister stated.

“The border plan that we introduced in 2024 December, which has been implemented now over the last 18 months, is bearing fruit,” he said.

Anandasangaree also highlighted close collaboration between Canadian and American authorities.

“The cooperation amongst law enforcement, whether it’s DHS and Canada Border Services, or the operations centre where we’re embedded in Detroit, it’s critically important and we’re seeing that bearing fruit for security,” he said.

Concern About Cartels Moving North: Mullin

Mullin said that in addition to terrorist-related threats and illegal immigration, the U.S. government is highly concerned about the flow of fentanyl and cartel activity through its northern border.

“Over the last year we’ve apprehended enough fentanyl that would kill 17 million Americans on our northern border,” he said.

Mullin said he believes an uptick in organized crime activity at the Canada-U.S. border is due to stricter enforcement at the U.S.-Mexico border and “pressure we’re putting on the cartels” that is causing them to seek out “other areas.”

“We see the amount of increase of criminal activity that’s happening. And we see the same techniques that were on the southern border that are moving to the northern border,” Mullin said.

He said that cooperation between the United States and Canada is “vitally important” and pointed to intelligence-sharing between the two nations as the top priority.

“Our biggest priority now is to have great partnerships with our friends to the North to be able to actively stop [illegal activity] before it grows to the point that it is in Mexico,” he said, adding “the biggest issue that we’ve really got to work on is sharing the intel and then acting on it in a timely manner.”

Canada-US Tensions

At one point, Mullin compared the Canada-U.S. relationship to marriage, saying that current tensions are similar to when he and his wife get into an argument.

“It’s kind of like my wife and I when she gets really mad at me, and I’m well deserved to get mad at, sometimes I just have to stop and say, ‘love you,’” he said.

“Arguing doesn’t help; it only allows us to be more vulnerable for somebody else to sneak in and take my beautiful wife away from me.”

Anandasangaree also emphasized close U.S.-Canada ties, saying they go beyond government cooperation to economic prosperity.

“We rely heavily on each other for both security, but as well as trade and commerce,” he said, adding that much of the $900 billion of trade that takes place between the two countries annually is done “in an orderly manner that benefits both of our countries.”

“What differences we have is negligible compared to what we have in common and the work that we’re doing together,” Anandasangaree added.

The minister also noted ongoing enhanced investments in border security in Canada including the hiring of 1,000 more RCMP and 1,000 more Canada Border Service Agency personnel announced in June last year, along with increased use of drones, helicopters, and surveillance technology at the border.

Anandasangaree also referenced close cooperation between the RCMP and FBI in working together to help lead to the arrest of accused transnational Canadian drug trafficker Ryan Wedding by Mexican authorities in January, in addition to a recent investigation by Peel Regional Police that led to 17 arrests in May.

Fentanyl

Mullin’s figures for fentanyl lethality appear to be based on the U.S. Drug Enforcement Administration’s calculation method for potential fentanyl deaths, which holds that 2 milligrams can be a potentially lethal dose for the average person.

Data from U.S. Customs and Border Protection showed very low fentanyl seizures at the Canada-U.S. border during the period from July 2024 through to February 2026, with Ottawa stating that “Canada is not a significant source of illegal fentanyl entering the US. Less than 1% of fentanyl seized in the US comes from Canada.”

The office of Canada’s Fentanyl Czar Kevin Brosseau cites U.S. statistics in noting that roughly 71,000 pounds of fentanyl were seized at the U.S.-Mexico border from 2022 to 2025, compared to approximately 134 pounds seized at the Canada-U.S. border or in its vicinity.

While Mullin emphasized the scale of fentanyl seizures at the northern border, Anandasangaree said the real source of the crisis is precursors manufactured overseas.

“The flow of fentanyl is not from the north to south or south to north; it is coming from overseas with precursors that enable dealers to manufacture and distribute in our countries,” Anandasangaree said, though adding that he agreed “fentanyl and the scourge of fentanyl is impacting both of our countries.”

Looking Ahead

In terms of the future of the Canada-U.S. relationship, both officials said they are confident that cooperation will continue despite political disagreements.

“If there are irritations, we need to just work through them. We will work through them,” Anandasangaree said.

Mullin echoed this, saying that despite current tensions, the two countries remain indispensable partners.

“What we have to do is quit focusing on our differences and start thinking about what we have in common,” Mullin said.