The number of illegal immigrants arrested at the United States border skyrocketed 400 percent in Maine in recent years, in part because of special electronic travel authorization with Mexico that allows Mexican citizens into the country without a visa.

Last month, border patrol agents patrolling the New Brunswick-Maine border arrested five men crossing illegally in a vehicle near Limestone, Maine: three Mexicans for illegal entry, another Mexican citizen for illegal re-entry, and an American citizen who was charged with alien smuggling, CBC reports.

“We’ve seen a pattern of this, not only in the state of Maine, but also among the entire northern border,” Jason Schneider, deputy patrol officers stationed in Houlton, Maine, told the news site.

Schneider explained that many of the illegal immigrants attempting to cross the northern border made their way to Canada under a special electronic travel authorization program that eliminates the need for a visa.

“It is safer, if you think about it,” he said.

“It is much safer and cheaper to be smuggled across the northern border, fly from Mexico into Canada and be smuggled across the northern border as opposed to paying large fees to the alien smuggling cartel organizations along the southwest border, and it’s not as dangerous.”

Jason Owens, chief patrol agent for USBP’s Houlton Sector, discussed the often overlooked northern border in a video posted to Twitter on Monday.

“Another busy weekend for #USBPMaine. Several arrests involving border incursions in this area,” Owens wrote in the post. “Very remote, very cold (14 degrees), lots of snow … doesn’t matter. The answer is, yes. Illicit cross-border activity is happening in #Maine.”

Owens said he made the video in response to repeated questions about activity in the area.

“The reason I brought you to this area is because this area of operation, not far from where I’m standing, ya, we have a couple of Vietnamese nationals that crossed the border right here. They were being smuggled by a couple of Colombian nationals,” he said.

“We had a methamphetamine seizure that was being smuggled across on snowmobile. We had some Mexican nationals that were just apprehended not too many days ago that took advantage of the ETA program with Canada to come up here and actually come across illegally,” he continued.

“So the answer to the question is, yes. There’s all kinds of traffic going on all along the border to include Maine in the winter months.”

It’s the same situation in Vermont, where NPR last year highlighted how tightened border security is driving the increasing arrests there and in other states.

“In 2017, CBP agents caught 165 immigrants; this year they took 822 people into custody in the sector that includes Vermont and parts of New York and New Hampshire,” according to the November 2019 report.

“They’re feeling a lot more pressure than they ever have down south, and they found loopholes to exploit via Canada,” Richard Ross, the patrol agent in charge of the Newport Station, told NPR. “It definitely has an effect on what we see up here.”