The thing is the police have unlimited backup, and better gear than any criminal group. They can call to state police, neighnoring departments. They have militarized gear, literally military surplus, and they can call for national guard backup, that has masses of armoured vehicles, machine guns, all sorts of heavier equipment. More helicopters with machine guns on them, all sorts of stuff. Drones. Then if the police needed help they could ask for militia help, even deputize some of them.

The security services are not lacking for firepower, it would be the worst mistake a cartel ever did if it tried this in the US, political leaders would crusade against them.