It didn't take much to turn a pleasant, pre-holiday weekend at Simon Property Group's Tacoma (Wash.) Mall into a retailer's worst nightmare. It just took one angry man.

Dominick Sergio Maldonado, 20, of Tacoma walked into the center with an assault rifle and a semi-automatic machine pistol, according to prosecutors, shot off 20 rounds and wounded six people. Maldonado then ducked inside a Sam Goody Music Store taking four hostages.

Four hours later, Maldonado allegedly was talked down by two of the hostages and gave himself up to police. Tacoma Mall was reopened the following day.

While an isolated incident, the event underscores how vulnerable the nation's malls are to random acts of violence and terrorism. Maldonado appears to have had even ghastlier intentions as police found bomb blueprints and a formula for making the poison ricin in his car and bedroom.

Since 9/11, the mall industry has tried to increase security awareness to stop terrorist attacks or isolated acts of violence from mentally unstable individuals. “Security is always our primary concern for shoppers and retailers on our properties across the country,” says a spokesman for Simon. However, some critics argue the industry hasn't done enough. (For more information on mall security, check out “Targeting the Mall,” in our September issue at www.retailtrafficmag.com.)