Sgt. Kevin Nixon said the animal had a severe tick infestation and was weak and lethargic as a result.
"We tranquilized the moose and attempted to relocate it. Unfortunately, given its shape and its health, it didn’t make the relocation process. We took it out of town and monitored it for a few hours and it unfortunately didn’t make it," he said.
He said the animal was a problem moose that had been seen several times in the city, and had exhibited aggressive behaviour.
The moose became an overnight sensation after customers shot a video of it wandering through the flower section of Safeway before eventually being guided out of the store by an employee with an apple.
Officials say they will investigate reports that people were feeding the moose outside the store.
"We can’t have the public feeding wildlife. We could have had a very dangerous situation on our hands had that moose been trapped in the store or started to freak out," Nixon said.
Harold Gyger was in the parking lot when he saw first saw the moose.
"People were feeding it outside, rolling apples back and forth trying to get it to eat them. And it was eating them, and it was very, very disturbing. They should've just left it alone," Gyger said.
"And at that point, then, the moose started following people in the store and walked completely in the electronic doors."
Customer Hannah Dehoog shot a video as a store employee eventually guided the moose back outside.