A Cook County sheriff's deputy on helicopter patrol Tuesday said he spotted the plants growing amid weeds because he had "the right altitude and the right angle, the right sunlight and happened to be glancing down," the Chicago Tribune reported.
"The plants are pretty big. They're as big as Christmas trees," Chicago police Lt. Michael Ryle said. "Some of the plants are as tall as 10 feet tall."
Police Superintendent Garry McCarthy said investigators did not know yet who was growing the pot but he said "spending that much time and effort setting up an operation like this in a place like Chicago, it is brazen."
Police were at the site Wednesday destroying what the Chicago Sun-Times reported was the largest pot operation ever in the city.
"Whoever harvests this marijuana is obviously running a large-scale operation, and at the same time, the profits from that will be used to purchase firearms, and that's where the violence comes in," McCarthy said.