(NewsNation) — A new caravan of about 1,500 migrants has begun its journey from Tapachula, Mexico, near the Guatemalan border.

Traveling at night to avoid the heat, the group includes families and individuals from Venezuela, Cuba, Haiti and Central America.

However, the migrants’ actual chances of reaching the southern border are slim to none as Mexican immigration authorities continue to step up their efforts to deter and block migrant groups from even reaching Mexico City. Sources tell NewsNation authorities have dubbed this “Operation Carousel” and that they are breaking up migrant groups and negotiating with them to travel to other Mexican states.

Authorities broke up two other small caravans headed to the United States over the weekend.

After a call with President-elect Donald Trump, Mexico’s President Claudia Sheinbaum reaffirmed Mexico’s commitment to controlling migration, stating migrants are “taken care of further south.”

However, Sheinbaum rejected Trump’s suggestion to deploy U.S. troops in Mexico to fight cartels, calling it a violation of sovereignty. Instead, she offered intelligence-sharing and collaboration.

For migrants, the trek is not just difficult but life-threatening. With Mexico cracking down and Texas building barriers, migrants face tougher choices and greater risks. Migrants told NewsNation that they face extortion by criminal groups, kidnappings where families are forced to pay ransoms and dangerous routes like Reynosa, which are controlled by cartels.

Migrants concerned over Trump policies

With Trump taking office next year, many migrants have grown nervous about his plans, including mass deportations and ending the CBP One app. The app is a critical tool for scheduling asylum appointments and one of their last hopes for legal entry. It offers around 1,450 appointments every day.

Meanwhile, Texas is working on constructing a 1.5-mile wall in Starr County, set to be finished by Christmas. Abbott recently released a new video showcasing the progress of the wall, which is being built on land Texas purchased. This same property was also offered to Trump for deportation facilities aimed at speeding up removals.

The wall, which costs $25 million per mile, is part of Operation Lone Star. So far, $11 billion has been spent on the program. The high price has raised questions about its effectiveness and how long it can continue.

The Associated Press contributed to this report.