Border Patrol agents in the Laredo Sector discovered 36 illegal immigrants packed into a tiny stash house while assisting officers from the Laredo Police Department on Monday.

Special Agents from U.S. Immigration and Customs Enforcement’s Homeland Security Investigations division contacted the Laredo Station about suspicious activity in a house located near Slaughter Park. The park is a known location for smuggling humans and drugs across the border. The agents went to check out the house with the help of the local police department, according to Laredo Border Patrol officials.

After making entry into the house, the agents found 36 illegal immigrants stashed inside. The migrants came to the U.S. from Guatemala, Mexico, El Salvador, and Honduras, officials stated.

“The partnerships in Laredo between the United States Border Patrol, Homeland Security Investigations, and the Laredo Police Department continue to show results in disrupting criminal organizations from operating in South Texas. We will continue to work with our law enforcement partners to prosecute those responsible and prevent individuals from being subjected to deplorable conditions,” Laredo Sector Assistant Chief Patrol Agent Gabriel Acosta said in a written statement.

Homeland Security Investigations is leading the investigation into the possible human trafficking charges that could be filed.

The migrants are now subject to prosecution in criminal court for illegally entering the U.S. according to a “zero tolerance” policy put in place by U.S. Attorney General Jeff Sessions on Monday.

The attorney general said his department will refer anyone who enters the United States illegally for prosecution, Breitbart News reported.

“And the Department of Justice will take up as many of those cases as humanly possible until we get to 100 percent,” Sessions said as part of a speech at a law enforcement conference in Arizona.