NEW BRUNSWICK - The wave of immigration raids and document checks in New Brunswick on Thursday led to six arrests in what federal officials say was targeted effort to locate and deport gang members.

"ICE's Homeland Security Investigations arrested six people in New Brunswick on Thursday for civil immigration violations," U.S. Immigration and Customs Enforcement Lou Martinez said in a statement.

"Those arrested are members or associates of transnational gangs. HSI regularly conducts gang enforcement operations across the country to enhance public safety," he said.

Martinez declined to identify those arrested. It was unclear if any of the people picked up had prior arrests or had been previously ordered deported.

The detentions led some activists to question how they went down.

ICE officials detained people at their homes, on their way to work, and one man who was allegedly stopped and arrested by authorities after visiting his probation officer, according to community leaders.

Teresa Vivar with LAZOS America Unida, a nonprofit advocacy group in Middlesex County, said multiple witnesses told her of federal authorities stopping people, showing them a photo of the person they were looking for and asking to see their identification.

"None of these people were connected to gangs or had criminal records," Vivar said the families told her. The officers were wearing yellow t-shirts with "Gang Unit" printed on the back, according to accounts of the incidents told to Vivar.

ICE officials did not respond to calls for details.

"The sad reality is that peaceful, law-abiding residents in the state are now in a precarious position of living in fear," said Analilia Mejia, the executive director of Working Families, a progressive political group that lobbied for city officials to adopt a sanctuary city distinction earlier this year.

"Having an undocumented population living in fear will have an impact on all of our public safety and the economy's bottom line, whether people realize it or not," she said.

City police were notified on Thursday morning by the Department of Homeland Security that ICE officials would be in New Brunswick later that day, according to police spokesman Capt. J.T. Miller.

"They did not request any assistance from the New Brunswick Police Department and no assistance was provided," Miller said via email.

The Middlesex County Sheriff's Department was not involved in the arrests, county officials said.

Craig McCarthy may be reached at CMcCarthy@njadvancemedia.com. Follow him on Twitter @createcraig and on Facebook here. Find NJ.com on Facebook.

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