Authorities couldn't help seeing similarities to the Columbine High School shooting after a fire forced the evacuation of a mall just two miles from the notorious campus.
Just like Columbine, an unexploded pipe bomb and propane tank were discovered Wednesday at Southwest Plaza Mall.
In addition, the blaze coincided with the 12th anniversary of the deadly shooting that left 12 students and one teacher dead.
"We're concerned about the date, the time, things of that nature, but we don't have anything solid that would indicate any link at all other than, certainly, circumstances," Jefferson County Sheriff Ted Mink said Thursday.
Authorities were investigating the cause of the fire, including whether it was sparked by the failed detonation of the bomb, West Metro Fire Rescue spokeswoman Cindy Matthews said.
No arrests have been made, but dozens of law enforcement agents were scouring security video and following other leads to identify a man seen entering the mall through a side door not normally used by the public.
No one was injured at the mall, and the bomb didn't explode. The mall reopened Thursday. Security guards were on patrol but it seemed like a normal shopping day.
Mink said the community shouldn't feel threatened, hinting that progress was being made in the investigation.
The two propane tanks found at Southwest Plaza Mall were discovered in a hallway of the food court after the fire was reported around 11:50 a.m. Wednesday.
The Columbine shootings started at 11:12 a.m. and ended 24 minutes later on April 20, 1999. Unexploded pipe bombs and a propane tank with explosives attached were found in the school cafeteria after the shooting.