Latvian authorities have discovered a tunnel used by migrants to cross the border from Belarus, amid long-standing concerns that Minsk is weaponizing migration against the EU. On Monday, border guards detected 15 people who had come through a 10-meter-long tunnel near the border fence between Belarus and Latvia, Riga’s Interior Minister Jānis Dombrava said Tuesday. Tunnels have previously been found in Lithuania, but this is the first time one has been used to cross into Latvia. "This is the first case in which a tunnel has been used for illegal crossing of the state border into Latvia. No signs of violations had previously been detected in this exact location, and no detentions of persons illegally crossing the state border had occurred there," Dombrava wrote on X. Authorities returned all 15 people to their “country of departure” and are continuing to inspect the area around the tunnel. Latvia launched an operation Tuesday to strengthen border security. Dombrava has described illegal border crossings from Belarus as a “hybrid threat.” Authorities have prevented more than 9,000 illegal attempts to cross the border from Belarus so far this year, the Latvian State Border Guard said in a press release. Prime Minister Andris Kulbergs stated that criminal networks are instrumental in moving migrants from Belarus into the EU's Schengen area, with their ultimate destinations lying elsewhere on the continent. He pledged to target these networks and any migrant support points within Latvia as part of a new initiative called "Operation Werewolf." Kulbergs expressed confidence that this operation would significantly disrupt the smuggling system. Latvia intends to collaborate with neighboring countries, including Estonia, Lithuania, and Poland, to curb the influx of migrants.