(NewsNation) — Illegal crossings at the U.S.-Mexico border are down from a record high in December and a crackdown by Mexican authorities is a major reason why.

Through the first two months of the year, Mexican officials encountered or apprehended 240,000 migrants, up 20% from previous monthly highs, according to Mexican government data cited by the Washington Office on Latin America (WOLA).

Mexico has also issued significantly fewer humanitarian visa cards in recent months. The number of those cards — which allow migrants to travel across the country — has plummeted 98% from an average of 13,294 per month for most of 2023 to just 213 per month between November and February, WOLA noted.

The recent crackdown has been apparent in the northern border state of Chihuahua where Mexican patrols have become more visible along the Rio Grande in Ciudad Juarez. That effort comes as hundreds of migrants continue to ride trains to the El Paso-Juarez border to seek asylum in the U.S.

Over the weekend, President Joe Biden and Mexican President Andrés Manuel López Obrador discussed new steps to clamp down on illegal migration — a plan that reportedly includes tougher enforcement on railways, buses and in airports.

Along the southern border, illegal crossings are down more than 40% from December to March, according to data from U.S. Customs and Border Protection (CBP).

“The teamwork is paying off,” White House national security spokesman John Kirby said Tuesday. However, he warned that border encounters tend to increase in warm weather months and said the administration will continue to work with Mexican authorities.

Other reports suggest Mexico’s stepped-up enforcement is just delaying, rather than blocking, illegal migration to the U.S.

“Most detained migrants are swiftly freed because of legal protections, and a lack of resources for the sheer numbers crossing mean many eventually make it across the border,” the Financial Times noted last week.

Of the nearly 120,000 migrant detentions in Mexico in January just 3,000 were moved to another country, the media outlet reported. Rather than get expelled, most were given an administrative order and told to leave before eventually being released into the country.

Of particular concern are the migrants crossing the Darién Gap in Panama, a treacherous passage that’s grown in popularity and saw more than half a million people pass through last year.

In other words, even if Mexico cracks down, broader enforcement in other Latin American countries may be necessary to stem migration flows from further south.

“There must be a huge number of people from Venezuela bottled up in Mexico right now,” Adam Isacson, an analyst of border and migration patterns at WOLA recently told NPR.

Panama’s government said it removed 864 migrants from the country between April 2023 and April 2024, Isacson wrote in a recent report. Meanwhile, Guatemalan authorities have expelled nearly 7,735 migrants into Honduras and an additional 177 into El Salvador so far this year, the report noted.