The counter-insurgency program was a security measure designed for a hypothetical revolt by Bajoran laborers aboard Terok Nor.
It was installed by its commanding officer, then-Gul Dukat during the Occupation of Bajor because the Bajorans far outnumbered their Cardassian overseers. The program was designed so Dukat and his fellow Cardassian officers could interact with and control it, but if necessary, it could run independently. To ensure smooth operation, the program had several levels of severity to allow it to deal with a variety of scenarios, the focus being a revolt by laborers in ore processing. Naturally, Dukat omitted mention of the program's existence when control of what was now called Deep Space 9 passed to Benjamin Sisko in 2369.
If the workers escaped or the insurgency spread and resulted in an escape from ore processing, the program was set to take control of the station. Force fields would secure sensitive areas of the station's computer circuitry, Ops and the security office, with similar force fields blocking access to virtually every major doorway on the station.
The program was discovered by Miles O'Brien, and Jake Sisko in 2371 while investigating the possibility of turning the ore-processing area into a deuterium refinery. Lack of knowledge about the program caused the crew to activate the program's higher levels once the station-wide program took effect...