Santa Ana police detained 21 people on Tuesday morning after raiding a cyber cafe that was allegedly being used as an illegal gambling facility, authorities said.

Investigators made entry into the Lucky 999 Cyber Internet after serving a search warrant at the business around 6 a.m., according to Santa Ana Police Department Cpl. Anthony Bertagna.

Inside, they found 21 people packed into the 700- to 800-square-foot facility, Bertagna said.

All were detained, although it was not immediately clear how many would be arrested or cited, or whether any would face charges, according to the corporal.

Two people accused of running the operation are expected to be booked, as is one individual who was found to have an outstanding warrant, Bertagna said. Those suspected of committing misdemeanors will be cited and released.

Nineteen gambling machines were also seized, the majority of which did not have internet access, according to police.

“This is an illegal operation, they don’t have a business license,” Bertagna told KTLA.

The raid was the culmination of a yearlong investigation that began after the department received numerous complaints about the 24-hour establishment, which is located in a part of a city that is typically quiet in the evening. Nothing else is open in that specific area at night except for the internet cafe, according to investigators.

“We’ve gotten several cases from the gang unit where they’ve gotten individuals in possession of firearms, possession of narcotics, we’ve had pursuits out of this location,” Bertagna said. “Patrol officers have also come across several individuals with handguns. So it’s a quality of life issue.”

The corporal explained it took one year to build the investigation and tie it to the location in order to obtain a search warrant to go inside.

This is the second internet cafe to be raided in the past seven months in Santa Ana.

Last September, eight people were arrested after a SWAT Team entered the Happy Times Cyber Internet Cafe as part of an investigation targeting gang activity and guns.

Police have not linked the two incidents, but they did note that similar operations have been known to reopen at a different location after being shut down.

“They’re a lot like the marijuana dispensaries were,” Bertagna said. “They pop up and then we close them, often times they reopen some other location.”

He added, “It’s growing throughout the state; it’s not just in our city, it’s everywhere.”