As CBC Windsor was first to report, the Canadian Border Service Agency recently raided a farm in Kingsville, where agents apprehended six temporary foreign workers from Thailand.

A CBSA spokesperson said the six people were "unauthorized workers at a farm in Kingsville."

"The investigation resulted in six arrests of undocumented foreign workers," Jean D'Amelio-Swyer wrote in an email to CBC News. "All individuals are being processed in accordance with Canadian immigration laws."

Canada's Temporary Foreign Worker Program has been under scrutiny since CBC News first learned the Royal Bank of Canada replaced some of its Canadian staff with workers from India.

Chris Ramsaroop is an organizer with Justicia/Justice for Migrant Workers, a Toronto-based non-profit that "strives to promote the rights of migrant farmworkers."

He told CBC News raids of this kind are not uncommon in the region.

"It seems that this is — particularly in southwestern Ontario, particularly in Leamington, Kingsville, Essex County — that this is a weekly or every other week occurrence," he claimed. "We're always hearing about people being picked up or CBSA, Canadian Border [Services] agents, going to different farms and greenhouses, trying to detain non-status residents."

The CBSA did not tell CBC News the number of raids they conduct. However, the CBSA did say twenty-seven people were detained in 2012 in Windsor and Sarnia. In CBSA's Southern Ontario region there were fourty-five people detained in 2012.

The Temporary Foreign Worker Program allows workers to come to Canada for employment for a year or two. However, when the permit is up, employees have two options: try to get the permit renewed or go home.

Dia Chueawongsa has been legally working for Highline Farms of Leamington for five years.

She claims "recruiters" approach temporary foreign workers when their permit is up with a simple pitch: money.

'You don't have to pay tax'

"You work here, you don't make too much money. You go to a job on another farm, then you'll have more money. You don't have to pay tax," Chueawongsa said.

She claims recruiters and some employers pay in cash. That would mean no tax deductions, and no contributions to Employment Insurance or the Canada Pension Plan — all of which temporary foreign workers contribute to.

Chueawongsa claims illegal workers are often housed by the agency that recruited them, and go to great lengths to avoid discovery.

Chueawongsa estimates there are at least 25 of illegal workers in the Leamington area.

Chueawongsa calls the workers "skippies." They're often moved from place to place to keep them from being found, she claimed.

"Individuals working illegally in Canada undermine the integrity of our immigration system and hurt those foreign workers who abide by our laws. Any foreign national working illegally in Canada may face criminal charges and may be issued a removal order. As well, companies that hire illegal foreign workers may also face criminal charges," D'Amelio-Swyer wrote.

She said the CBSA works closely with other law enforcement agencies "to detect, apprehend, and remove individuals that do not have the authority to be in Canada."

'Integrity of program important to CBSA'

"The CBSA is responsible for the enforcement of the Immigration and Refugee Protection Act (IRPA) and regularly conducts investigations into possible violations of the IRPA when there is evidence or information of a violation. This includes investigating foreign nationals who are working without authorization and/or employers hiring or employing improperly documented workers," D'Amelio-Swyer wrote. "The integrity of temporary foreign worker program is important to the CBSA."

CBC News has confirmed the six workers picked up in Kingsville spent a week in Windsor Jail before being moved to Toronto.

John Rokakis, an immigration and refugee lawyer from Windsor, said there used to be an immigration detention facility in Windsor, but it closed years ago due to budget cuts.

He hopes cases like these will convince the government to re-open a similar facility.

"They're not, in the true sense of the word, criminals. They really shouldn't be in a jail, so having them go to Toronto, in a way, is better than having them in Windsor because in Toronto they're not at a jail, they're at a immigration detention facility," he said.

Despite calls to the Canada Border Services Agency, Citizenship and Immigration Canada and the Royal Thai Embassy, CBC News has been unable to learn the ultimate fate of the workers and whether they have been deported.