Dozens of New Jersey warehouse workers are in federal custody following a midweek raid.

It follows a similar operation in Edison that happened in July.

At least 50 workers questioned by federal agents, witness says

Witnesses say Wednesday morning, about 25 vehicles, both marked and unmarked, pulled into a complex of warehouses along Patrick Avenue. It is unclear which Edison warehouse along the crowded strip was being targeted.

In Spanish, one man who was working inside at the time told CBS News New York at least 50 coworkers were questioned by federal agents. The man, who did not want to be identified, said he showed them his documents and was let go, but he says dozens were taken into custody.

"They don't ask you if you have it or don't have it. They put you in handcuffs," another worker who wanted to remain anonymous said in Spanish.

That worker said, without explanation, he was placed in handcuffs, then asked if he had documentation, which he says he did. He was then set free, wearing a yellow wristband. He said his leg was injured during the chaos of the raid.

"Worksite enforcement remains a cornerstone of our efforts to protect public safety, national security, and economic stability while rescuing individuals who may be victims of labor trafficking or exploitation. These operations target illegal employment networks that undermine American workers, destabilize labor markets, and threaten American communities," the Department of Homeland Security told CBS News New York in a statement late Thursday night. 

U.S. Senators Cory Booker and Andy Kim, of New Jersey, released a joint statement saying, "We condemn this raid as these actions run counter to New Jersey's values of building safe and thriving communities."

"This is extremely un-American and illegal. We understand that Customs and Border Patrol has the contract with the warehouse, but ICE still needs a judicial warrant signed by a judge in order to go and enforce immigration-related actions," said Amanda Dominguez, a community organizer with the immigrant advocacy group New Labor New Jersey.

Dominguez added, "We're seeing families forcibly separated ... Many of these workers did not realize that they worked at CBP-bonded facilities that would allow these entities to come into their workplace at any time."

2nd raid at Edison warehouse in 2 months

This was the second raid at an Edison workplace in as many months. The last one was on July 8. That's when 20 people were taken into custody at the Alba Wine and Spirits warehouse in Edison.

"ICE is not telling families where they can find individuals," Dominguez said. "And so families don't know how to find them, how to get them out, how to support them financially."

Before the latest raid, the Edison Township Police Department got a heads up from DHS that agents would be in the area, according to the Edison mayor's office.