I used to patrol the air in the police helicopters we built for them in the early 2000's. There is a standing no fly zone over the red light district, for fear of nervous customers being scared away. There primary concern was not hookers and drugs, but illegal commerce for general merchandise. I tracked semi trucks using advanced IR tracking and advised the ground. I also went window shopping in the district, funforgettable times I tell ya. The smoke shops were supposed to be off limits to me, but ya know how that goes. lol