Police said they received tips Thursday that prompted an all-night investigation that eventually led investigators to the home on Friday.
"When we got into the house we realized that there were over 90 people inside," Assistant Chief Daryn Edwards told reporters.
The department's SWAT team entered a house at 12210 Chessington Drive and the kidnapping investigation soon became a "disturbing" human smuggling case, Edwards said.
Property records show the address contains a 2,319-square-foot home with five bedrooms and two baths. Neighbors told police they were unaware that so many people were inside. It was being rented to a single man.
Multiple people inside reported possible coronavirus symptoms including fevers and loss of sense of smell.
"We are concerned that there may be some positive COVID cases inside the house," Edwards said.
Police called in the health department to screen for possible COVID-19 cases and were weighing quarantine options as the victims received medical care inside the house.
They also provided food and water.
U.S. Customs and Border Protection says one in four victims of human trafficking or modern-day slavery are children – and the majority of forced laborers, including forced sex workers, are women and girls.
Houston police found only five females at the home on Friday and the rest were males, Edwards said. None of the victims were children.
"This is definitely more of a smuggling thing and not a trafficking thing," Edwards said.
But he said members of the public should keep their eyes open for any sort of suspicious activity and report it to investigators -- because what they find could be surprising yet again.
Texas alone saw more than 1,080 human trafficking cases reported in 2019, the most recent year with data available, according to the Human Trafficking Hotline. More than 800 of those involved in sex trafficking and almost all of the victims were female.