United States Border Patrol arrested 7 migrants on Tuesday who allegedly crossed illegally into Maine from Canada.

Maine State Police pulled over a vehicle in Bridgewater, near the Houlton port of entry on Maine’s northern border, that was reportedly seen “crossing the center line on four separate occasions,” according to a Border Patrol affidavit, the County reports.

The vehicle was reportedly transporting eight individuals at the time of apprehension. Border Patrol agents arrived on scene shortly after at approximately 10 p.m. to help with linguistic translation.

Four of the vehicle’s passengers were charged with a misdemeanor for entering the United States illegally, and three others were charged with felonies for illegal re-entry, according to Border Patrol. Illegal re-entry is a class E felony that is punishable by “a fine under title 18, imprisonment for not more than 2 years,” according to the Department of Justice.

All of those arrested were confirmed to be Mexican nationals, according to the County.

Border Patrol has experienced a “three-fold increase” in apprehensions of Mexican nationals since last year, according to Houlton Border Patrol public affairs liaison, Mark Philips.