Immigration activists in Vancouver are protesting the arrest of eight migrant workers who they say were picked up by border agents and filmed for a reality TV series during a raid on a construction site on Wednesday.

Construction worker Gord Beck says he was working on a condo complex at Victoria Drive and 20th Avenue when armed border agents arrived in black SUVs.

Beck says they stationed officers at corners to keep people from running, and swept the site, top to bottom looking for undocumented workers.

"I've worked with a lot of guys with ankle bracelets and stuff, but I've never seen Immigration swamp a site like that," Beck told CBC News.

Oscar Mata, who is originally from Mexico, was found hiding in a closet at the construction site by border officials.

"I go out and ask ‘why is the camera? He said ‘Oh don’t worry, is a reality show,’" Mata told CBC News.

Mata came to Canada five years ago. But when his student visa expired, Mata says he stayed illegally. He had been working at the site for the last three months.

Mindy Shepard, who was working across the street at the time, said she was shocked to see TV cameras recording up to a dozen arrests.

"It doesn't seem very Canadian. It's very sensationalized. I don't like it. It's just very creepy," said Shepard.

The immigrant advocacy group No One Is Illegal says there were at least three such raids in the region on Wednesday and some of those arrested were asked to sign release forms so they could be identified for the reality TV program.

On Thursday, the Canada Border Services Agency (CBSA) declined CBC's request for an on-camera interview.

In a written statement, a spokeswoman said officers conducted just one raid on Wednesday and had visited the construction site to locate a previously deported person with a long criminal history. The detained men were found by chance, the spokeswoman said.

"CBSA has a responsibility to protect the safety and security of Canadians by locating, arresting and removing individuals who pose a threat to public safety, who are subject to an outstanding immigration arrest warrant and who are in violation of the Immigration and Refugee Protection Act, such as working without authorization," the statement read.

Construction workers at this site in East Vancouver say it was raided by immigration agents on Wednesday. (Steve Lus/CBC)

The CBSA also said that participation in the television series is strictly voluntary.

"An individual’s case will not be negatively or positively impacted by their decision to participate or not," the statement read.

Documentary vs. reality series

According to the show's website, Border Security: Canada’s Front Line is produced by Shaw Media in Vancouver and shadows CBSA officers working at air, land, and marine crossings in B.C.’s Lower Mainland and Vancouver Island.

The show is broadcast on the National Geographic Channel and is produced by Vancouver-based Force Four Entertainment.

On Thursday afternoon, Force Four Entertainment spokesman Andrew Poon issued a written statement, calling the show a "documentary series."

"Yesterday's events occurred as we were documenting the day-to-day activities of the CBSA's inland enforcement team and were in no way planned or staged," Poon wrote.

"We would not sensationalize any situation for this series. Border Security is a documentary, not a reality series."

Poon said no one will be identified in the programs without their written permission and even with consent, their names will not be revealed.

Poon also said that "no one is filmed without their advance verbal permission."

Protesters call filmed raids 'dehumanizing'

A scene from Border Security: Canada's Front Line, a show on the National Geographic Channel. (National Geographic Channel)

On Thursday, a group of protesters held a noon-hour rally outside the federal immigration office in downtown Vancouver to call for an end to the filming of the TV show featuring border agents and an end to "intimidation raids at construction sites."

Diana Thompson, the wife of a Honduran worker who was detained, said her husband was asked to sign a release form for his consent to be filmed but he refused.

"Disgusted," Thompson said, choking back tears. "It's already a horrible situation ... and I feel that they make the matter even worse."

Organizer Harsha Walia called the raids intimidation tactics that have no place in Canada.

"The fact that watching people being detained and arrested and humiliated and interrogated becomes something that we consume as part of our nightly entertainment – there is something deeply troubling about this and very dehumanizing."