Columbia Mall employees holding carnations walk towards the doors of the mall which is expected to open in the afternoon on Monday Jan. 27, 2014, in Howard County, Md. Three people died Saturday in a shooting at a mall in suburban Baltimore, including the presumed gunman. A makeshift memorial sits outside the Mall of Columbia, Md., Monday, Jan. 27, 2014, after a weekend shooting that left three people dead, including the gunman, is set to reopen with increased security. (AP Photo/Jessica Gresko (AP) - The mall where a Maryland teenager gunned down two people before killing himself has reopened to shoppers. The Mall in Columbia opened at 1 p.m. Monday, two days after a man with a shotgun killed two employees of a skateboard gear shop. The Zumiez store where the shooting took place was covered by white boards as if the shop was under construction. Messages thanked first responders and encouraged people to leave condolence messages for the two slain workers. Crowds of shoppers were sparse in the early minutes of business, though white flowers were already scattered in a memorial fountain. Investigators are trying to determine whether 19-year-old Darion Marcus Aguilar knew the two victims. Police say an officer found a journal at Aguilar's home that "expressed general unhappiness."