The two teens, Eric Harris and Dylan Klebold, committed suicide after the massacre. They had left pipe bombs in the school but the majority of them did not explode.
It's unclear whether Wednesday's incident was connected to the shooting anniversary, but the mall is located near the high school.
"We're concerned about the date, the time and things of that nature, but we don't have anything solid that would indicate there's any link at all other than ... certainly circumstances," Jefferson County Sheriff Ted Mink said at a press conference Wednesday.
Late Wednesday night, FBI and law enforcement officials released a photo of the person of interest -- today identified as Moore -- who was spotted on mall security cameras.
He was wearing a dark cap, striped shirt, blue jeans and dark shoes. In the surveillance photos, he was seen holding a white plastic shopping bag.
ABC News' Pierre Thomas and Leezel Tanglao contributed to this report.