NEW ORLEANS — Two labourers stand on the roof of a house in Kenner, outside New Orleans, as US Border Patrol agents clamber up a ladder, getting closer.

As the agents move in, trying to arrest them, the men step to the roof's edge, poised in an apparent act of resistance - but it's too high to jump.

On the ground in the mostly Latino neighbourhood, an officer trains his weapon towards the rooftop while a sniper moves into position. Now, neighbours, activists, and crews of local press are gathering at the scene, watching in bewilderment: US President Trump's new front line on immigration enforcement has just arrived.

It is day one of "Catahoula Crunch", as the Department of Homeland Security (DHS) has labelled its operation, taking its name from an American leopard dog known for being well-muscled, powerful and territorial.

"These people came to work today to provide for their families and themselves," said Zoe Higgins, an activist documenting the Border Patrol operation in New Orleans.

"That they could just be abducted, removed from all stability - I can't imagine how terrifying that is," she said, shortly after the agents coaxed the men down and detained them.

According to DHS, its agents were conducting immigration enforcement this week when "several illegal aliens climbed on the roof of a residential home and refused to comply with agent commands".

An "illegal alien" was arrested, DHS officials told the BBC, but they did not answer questions about the immigration status of the labourers involved, nor whether agents had a warrant to access the property.

On Thursday, DHS reported in a news release that dozens of people who had either been arrested or convicted of various crimes were arrested in the Louisiana operation.

It is the fourth major city targeted in Trump's immigration clampdown, after he promised the biggest mass deportation operation of undocumented migrants in history. Strongly backed by his base, the campaign has sparked a fierce backlash in the Democrat-led cities it has targeted.

Still, Border Patrol commander Greg Bovino, who wears a flak-jacket and travels with enforcement teams, promised to target the "worst of the worst" among undocumented migrants.

He walked from the Homeland Security HQ in New Orleans, flanked by armed and masked enforcement agents. "Whether we do it on foot or in vehicles, in the air or in the water, this is what we do. So whether it's walking a beat, we're all about making America safe," he said.

According to media reports, officials aim to make 5,000 arrests in the city, focusing on criminals. But New Orleans City Council President JP Morrell said Thursday that "a sweep of New Orleans, or the surrounding parishes" would not "yield anywhere near 5,000 criminals, let alone ones considered 'violent' by any definition".

In Kenner, a New Orleans suburb, the Latino community is in lockdown for fear of the raids.

The door is unbolted at Abigail's, one of the few Mexican restaurants still serving, albeit mostly through deliveries these days.

Two decades ago aged 10, Abigail, who asked to only use her first name for fear of retribution, came to the US from Mexico City with her family. Since then, her parents, Sandra and Cesar, have built a restaurant business, catering to Kenner's vibrant mixed community.

But now her family sleeps in the restaurant, worried about getting caught up in the raids.

"All this business is from immigrants," said Abigail, whose son, 10, was born in the US. "A lot of people, they feel afraid to go out, they feel scared to go out. They feel so sad about this situation."

There are up to 14 million people in the US without legal permission, according to the most recent estimates by the non-partisan Pew Research Center.

Catahoula Crunch is targeting undocumented migrants who also face criminal allegations, Bovino said. The operation was announced with a press release showing mug shots of those it claims were released into the community and not into US Immigration and Customs Enforcement (ICE) custody due to "sanctuary" policies, in cities like New Orleans. However, leaked government figures from the last city targeted suggest most of those rounded up had no criminal past.

The term "sanctuary city" has become popular in the US to describe places that limit their assistance to federal immigration authorities.

An estimated 13% of New Orleans's one million-strong population is Hispanic. Many arrived to help rebuild the city in the aftermath of Hurricane Katrina in 2005.

As undocumented migration into the US surged under the Biden administration, particularly over the southern border, it became a core election issue and led to Mr Trump's campaign pledges for an aggressive deportation campaign.

Leaders in New Orleans oppose his tactics, but the Republican governor of Louisiana, Jeff Landry, welcomes them. Rounded-up migrants could be detained in "Angola", the Louisiana State Penitentiary and the US's largest maximum security prison. Its name is linked to the former slave plantation which was located where the prison now stands.

One of the world's longest bridges - nearly 24 miles long over Lake Pontchartrain - connects New Orleans to the north shore. In this Republican-dominated district, Trump supporters who back the operation live alongside those who think it's gone too far.

"A lot of them do work a lot harder than everyone else," said Tyler Forrester, a mechanic. "But if they're not here legally, they're not allowed to be here, they should get out."

Mary-Anne, another resident who voted for Trump and did not give her last name, describes the issue as "complex".

"I just have mixed feelings about it, because what if this mom is here with her husband who's legal and her children and she's working, why would you take her, as opposed to someone who has a [criminal] record," she said.

The mood reflects shifting views on immigration in Trump's own base.

Polling suggests the president's approval rating is sliding over his handling of the issue, as well as a sharp drop since last year in the number of Republicans who believe overall immigration rates need to come down.

Back in Kenner, the tensions and sense of uncertainty mounts again as another chapter is written in America's long story on immigration. — BBC