HOUSTON (AP) — U.S. immigration authorities on Thursday were interviewing more than 100 people presumed to be in the country illegally after they were discovered crammed into a small house in south Houston.

Five men also were in custody, two of whom were arrested after driving from the home on Wednesday. Authorities suspect it was a so-called stash house, a place where smugglers bring the people they've brought into the U.S. illegally and keep them until they or their family members pay a ransom.

Police who found handguns and documents in the car suggesting illegal activity then went inside and found the people captive. Three other men were apprehended trying to flee after police arrived.

U.S. Immigration and Customs Enforcement Special Agent Brian Moskowitz told a congressional hearing in Houston Thursday the five were held on offenses that included hostage taking, weapons charges and conspiracy to harbor illegal immigrants.

"It's going to take some time," agency spokesman Greg Palmore said. "We're not far along that we're going to release names at this point. We're still interviewing individuals and we'll follow the information where it goes.

"It's nothing that's going to occur overnight."

Men in underwear and without shoes, more than a dozen women and two children were found inside the filthy single-story, 1,500-square-foot house about 12 miles south of downtown Houston. They are primarily from El Salvador, Honduras, Guatemala and Mexico, Palmore said.

In a statement from Mexico City, the Mexican government said Thursday that at least eight of the people involved were Mexican citizens, including three minors who have been turned over to relatives. The statement did not specify if the five adult Mexican citizens were among those facing criminal charges or those held captive at the house.

Houston police, responding to a tip, went to the home in a somewhat rural area during a search for a 24-year-old woman and her two children, a 7-year-old girl and a 5-year-old boy. They'd been reported missing by relatives late Tuesday after an apparent smuggler didn't show for a planned meeting, police spokesman John Cannon said.

Officers found 115 people jammed inside. Among them were the missing woman and her two kids.

It was not immediately certain how the people got there, but one woman told authorities she'd been held for 15 days. Cannon said the other women said they'd been captive for several days.

Authorities are still determining whether the people will be deported, Palmore said.

The house had power but no hot water and only one toilet.

"It's a typical stash house-type of environment," Cannon said Thursday. "What was atypical was the numbers of people kept inside."

Stash houses are not uncommon in Houston, because of its proximity to Mexico, which is as little as a five-hour drive to the southwest. But the size of the operation discovered Wednesday is more prevalent closer to the border in South Texas.

Palmore described the number of people as "the largest I've seen in one location" in his seven years on the job in Houston.

"This case demonstrates the human tragedy that occurs as a result of our broken borders," said U.S. Rep. Michael McCaul, R-Texas, chair of the House Homeland Security Committee, who was in Houston Thursday for a hearing on human trafficking.

"Last year over 100,000 people entered the United States illegally through Texas alone and the Department of Homeland Security has no plans to stop the flow," he said.

In 2012, four people were arrested when 131 people were found in a house near Alton in Hidalgo County, about 8 miles north of the border. An additional 115 were discovered the same year nearby in a cluster of stash houses near Edinburg, also in the Rio Grande Valley.

"It's sporadic," Palmore said. "It's nothing you can predict. Some weeks we can encounter five days straight, five separate incidents. Then other weeks we may have none at all."