Acting Immigration and Customs Enforcement Director Matthew Albence defended his agency's raids across Mississippi last week, which left many children separated from their parents, saying those breaking the law were ultimately the ones to blame for the situation.

"We conduct our operations with professionalism, with compassion and with humanity, and we tried our best to minimize the impact on the innocent people of this situation," Albence said. "However, we have to enforce the law. Every law [enforcement agency] enforces the law against individuals who have broken it."

"The parents or the individuals that are breaking the law are ultimately the ones that are responsible for placing their children in this situation," he said.

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Immigration enforcement authorities raided food processing plants across Mississippi last week, picking up almost 700 workers — most of them Latino — in what could be the biggest single-day, one-state sweep in U.S. history.

The raids hit seven plants, owned by five companies, in six cities, leaving numerous children separated from their parents. Some of the children were just starting school, forcing them to turn to strangers or distant relatives for help as they waited for answers, immigrant advocates said.

When Albence was shown a video of a young girl crying because her parents were swept up in the raid, he emphasized that the separation of children from parents was a difficult part of enforcement.

"Look, I'm a parent, most of our officers and agents are parents — some of the most difficult things that we have to do in our jobs to enforce the laws involve the separation of parents from children," he said. "Every law enforcement officer has to deal with that at some point in their career. Many officers, on a daily basis — when an officer goes in to arrest somebody for a crime of domestic violence, one of the children in there is going to be crying."

As of Thursday, almost 300 detainees had been released from custody after being processed and given dates to appear in federal immigration court, according to Jere Miles, special agent in charge at the Department of Homeland Security in New Orleans, which covers Mississippi. Those who remained in detention were being held in Louisiana and Mississippi, officials said.