A mass shooting at a mall near Dallas on Saturday -- which left nine dead, including the suspect, as well as seven injured -- turned a shopping destination into a site of horrifying carnage.
The attack comes less than a year after a gunman opened fire at a mall in Greenwood, Indiana, killing three people and injuring two others. A few months before that, last April, a shooter at a mall in Columbia, South Carolina, injured 14 people.
Shopping malls offer a vulnerable target for mass shooters and a near-impossible task for security, since droves of people often converge through multiple entry points with easy access, experts told ABC News.
Moreover, efforts to better secure malls with metal detectors or additional security guards risk pushback from developers and stores forced to bear added costs as well as customers faced with the inconvenience of airport-style lines and armed surveillance, they added.
"People can get out of their car, walk into a mall and do mayhem inside," Kenneth Gray, a lecturer in the Criminal Justice Department at the University of New Haven, told ABC News.
Still, some malls may seek to find a balance between heightened security and consumer comfort, the experts said, noting that safety at such venues owes in large part to the wider context of gun laws and mental health services.
Simon Property Group, the real estate developer behind Allen Premium Outlets, the Allen, Texas, mall where the shooting took place, did not immediately respond to a request for comment.
A security guard, Christian LaCour, 20, was among the victims who died in the shooting.
"You want to have an open environment that's welcoming to people," Gray said. "At the same time, you don't want them to be sitting ducks."
Retail locations make up the second-most common site of mass shootings, accounting for nearly 17% of mass shootings recorded between 1966 and 2021, according to a previous ABC News analysis of data compiled by The Violence Project.
Workplaces, many of which are private commercial establishments, mark the most frequent location for mass shootings, the data showed.
The nation's roughly 700 malls are part of a category referred to as "soft targets," which includes religious institutions, restaurants and other locations.
Bolstered security at such locations would require checkpoints at every entryway as well as round-the-clock guards available to respond quickly in the event of an attack, Tung Yin, a national security expert and professor at Lewis & Clark Law School, told ABC News.
Such measures would call for malls to make a significant financial investment and consumers to tolerate inevitable delay and discomfort, Yin added.
"If you're going to have people jamming into these checkpoints," he said, "think about the impact that would have on day-to-day life."
Peter Eliadis, a former law enforcement official and founder of the firm Intelligence Consulting Partners, said religious institutions have recently flooded him with calls inquiring about threat preparedness trainings but he has received far fewer requests from malls.
"Think about a mall with 50 stores that want to do active-threat training -- who's going to pay for it?" Eliadis told ABC News. "Every store says, 'I'm not doing it, you do it. Oh, the landlord should do it.'"
Bolstered security at malls would not ensure their safety, experts said, since larger policies dictate key factors that contribute to mass shootings, such as the availability of guns and the screening of individuals with mental health issues.
"The upstream part is addressing mental health issues and other behavioral signs that someone is on the path to becoming a mass shooter," Javed Ali, a former official at the FBI and Department of Homeland Security and a professor at the University of Michigan, told ABC News.
"And the gorilla in the room is the whole gun control issue," he added.
ABC News' Miles Cohen and Ivan Pereira contributed to this report.