Mexico has pledged to crack down harder on illegal crossings, and more migrants are being halted in their journeys to the United States.

With the ongoing migration crisis, a key campaign issue ahead of the 2024 presidential election, the U.S. and Mexico issued a joint statement last month and ordered their national security teams to work together to implement measures aiming to clamp down on irregular border crossings. That has led authorities in Mexico to take a much tougher approach, tightening security along key routes used to reach the border.

In Chihuahua City in northern Mexico, hundreds of Venezuelan migrants are waiting for one of the freight trains to start moving north. They've traveled over 5,000 kilometers to get there, but these days, the route 366 from their makeshift camp to the U.S. border at El Paso is often the hardest part.

Diana Soto has already made three failed attempts to cross the harsh Sonora Desert, where the only highway is now heavily patrolled.

"We can't go on foot because the authorities catch us and bring us back here. Taxis offer their services for high prices, but some drivers are robbing people. We're stuck here," said Soto, Venezuelan migrant.

But even when trains move, they don't necessarily reach the border, as Melissa Rondon and her three small children found out when theirs was halted by the migration authorities.

"The train stopped in the middle of the desert carrying 2,500 of us. The locomotive detached and drove away, and we were stranded there for five days," said Rondon, another Venezuelan migrant.

Countering the migrant tactic of hitching rides on Mexico's freight trains has meant significantly slowing cross-continental railway logistics. The migrants said the trains haven't moved in two weeks.

Truck crossings at the border are also greatly reduced, which impacts U.S. trade flows, according to Luis Vargas, director of SCI, a logistics company specializing in imports.

"It's currently taking twelve hours for a truck to [cross into the U.S.] We're talking about billions of dollars in losses," he said.

The travel time used to be 90 minutes in the past, he added.

SHOTLIST:

Chihuahua City, Mexico - Recent
1. Aerial shots of city view, makeshift camp, trains;
2. Various of traffic, road sign;
3. Various of makeshift camp, migrants;
4. Security camera;
5. Makeshift camp, migrant;
6. Traffic;
7. SOUNDBITE (Spanish) Diana Soto, Venezuelan migrant (partially overlaid with shots 8-9):
"We can't go on foot because the authorities catch us and bring us back here. Taxis offer their services for high prices, but some drivers are robbing people. We're stuck here.";
[SHOTS OVERLAYING SOUNDBITE]
8. Various of Soto in camp;
9. Various of trains;
[SHOTS OVERLAYING SOUNDBITE]
10. Aerial shot of traffic;
11. Various of Venezuelan migrant Melissa Rondon;
12. Railway track;
13. SOUNDBITE (Spanish) Melissa Rondon, Venezuelan migrant (ending with shot 14):
"The train stopped in the middle of the desert carrying 2,500 of us. The locomotive detached and drove away, and we were stranded there for five days.";
14. Various of trains;
15. Sign for SCI, logistics company;
16. Various of employees at meeting;
17. Traffic;
18. SOUNDBITE (Spanish) Luis Vargas, director, SCI (ending with shot 19):
"It's currently taking twelve hours for a truck to [cross into the U.S.] We're talking about billions of dollars in losses.";
19. Various of traffic, cars lining up, trains;
20. Aerial shots of train moving.

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