Hundreds of migrants were filmed cheering triumphantly as they packed out a cargo train heading toward the US amid record numbers of illegal border crossings.

Footage posted by Fox News on Sunday showed a FerroMex train passing through the central Mexican city of Zacatecas as it made its way northbound on a 750-mile journey to the US.

Each cargo carriage was packed with people cheering, clapping and whistling in apparent triumph — with some even hanging from the sides and waving at the camera.

The footage quickly went viral after being tweeted by Fox News’ Griff Jenkins, who wrote that the migrants were “clearly not heeding the message: ‘do not come.’”

He was referring to Vice President Kamala Harris who told Guatemalan migrants in June: “Do not come. Do not come. The United States will continue to enforce our laws and secure our borders.”

The Post has reached out to US Customs and Border Protection for comment.

The video comes amid unprecedented illegal immigration to the United States.

In August, US Border Patrol officials arrested at least 91,000 migrants who crossed the border as part of family groups, according to data obtained by the Washington Post — beating the previous one-month record of 84,486 migrant families arrested in May 2019, under the Trump administration.

**NEW VIDEO**FOX News sources capture a FerroMex train bursting with migrants out of Zacatecas heading to our southern border right now… cheering and clearly not heeding the message: “do not come”@FoxNews pic.twitter.com/YflMwXrWqu

Officials also saw a marked increase in the number of unaccompanied minors crossing into the country.

The influx has inundated Border Patrol agents, who will likely soon start releasing migrants onto the streets of El Paso, Texas.

“Our No. 1 priority is the safety of our community and the safety of our asylum seekers,” Mayor Oscar Leeser said at a Friday morning news conference.

“We don’t want them sleeping on the streets, but at some point, we will run out of capacity.”

“Our No. 1 priority is the safety of our community and the safety of our asylum seekers,” Mayor Oscar Leeser said at a Friday morning news conference.

Until now, he said, the city government has been able to delay so-called “street releases,” when migrants who have been screened and processed by Border Patrol get released into the community when the agency runs out of space to hold them.

El Paso shelters that normally take the migrants in are at capacity, telling The Post in August they are “busier than ever.”

Leeser said the city has 400 dedicated hotel rooms every night available for migrants — paid for by federal tax dollars. Sometimes, the need is greater, as it was Thursday night when migrants filled up 700 hotel rooms.

In those cases, they can avoid having migrants on the streets by booking extra hotel space, but the rooms aren’t always available.

“The numbers continue to grow,” Leeser explained. “This has become something that we meet every day to prevent from happening.”

To deal with some of the influx, Texas Gov. Greg Abbott started busing migrants to so-called sanctuary cities, like New York, in April.

The goal was to force blue states to share the burden of the migration crisis.