Fear of law enforcement scrutiny and robbery has prompted several game rooms to force players to have "members only" ID cards. Other businesses have surveillance cameras watching who is approaching or a remotely operated cage at the front door that prevents people from walking in without first being screened by an employee.

Harris County sheriff's officials also said Houston's crackdown on these businesses is causing an unintended side effect.

"The more stringent Houston gets on these game rooms, this illegal activity, it's pushing it to the suburbs," said the undercover detective.

Sheriff's investigators estimate there are between 300 to 400 game rooms operating in the unincorporated parts of the county. Detectives said while the city can rely on numerous ordinances to regulate these game rooms, the county doesn't have the same restrictions. Investigators have to largely rely on state gambling laws.

"It's extremely frustrating and they're proliferating," said the undercover detective.

Sheriff's officials said they are now working with state legislators to try to craft tougher laws to regulate these game rooms.