(Adds details, quotes from shooter's neighbors)
By Alice Popovici
COLUMBIA, Md. Jan 26 (Reuters) - A gunman who shot and killed two people at a Maryland mall was a 19-year-old man who lived with his mother in the city of College Park and arrived at the shopping center in a taxi about an hour before opening fire, police said on Sunday.
But a day after Saturday's shootings, police could provide no immediate insight into why Darion Marcus Aguilar killed a young man and a young woman at the mall in Columbia, Maryland, about 20 miles (32 km) west of Baltimore, before apparently killing himself.
Police have yet to find any ties between Aguilar and the two people he killed, employees at a skate shop at the mall, Howard County Police Chief Bill McMahon told a Sunday morning news conference.
"We do know that one of our victims also lived in College Park," McMahon said. "We don't know if there's any connection there or whether that's merely coincidental."
Aguilar fired six to eight shots from a 12-gauge shotgun, killing Brianna Benlolo, 21, of College Park, and Tyler Johnson, 25, of Mount Airy, Maryland, police said.
Both were employees of Zumiez, the skate shop where the shooting took place. A third person on a lower floor of the mall suffered a gunshot wound to the foot, and four more people were hurt in the ensuing chaos.
The attack was the latest in a spate of shootings in recent weeks across the United States that have renewed questions about the vulnerability of public places like shopping centers, schools and cinemas.
U.S. Representative Michael McCaul, a Texas Republican and chairman of the House Committee on Homeland Security, said on Sunday that the latest shooting highlighted the vulnerability of malls.
"You can't have a security lockdown at our malls," he said in an interview with CBS, "but things like canines, a heavier canine presence are very good at detecting explosives."
"It's very difficult to stop a lone gunman who may have mental issues ...(and) wants to kill people. I mean, you can only do so much to stop that," he added.
The shooting in Maryland followed earlier gun violence at a New Jersey mall in November in which a gunman fired at least six shots without hitting anyone, sparking a mass evacuation of the complex, then killed himself.
The past week saw a student shot dead at South Carolina State University in Orangeburg on Friday, after a teacher's assistant was shot and killed at Purdue University in Indiana on Tuesday. Suspects have been charged with crimes in both cases.
SHOOTER AND VICTIM WERE NEIGHBORS
The Maryland shooting happened around 11:15 a.m. EST (1615 GMT) on the mall's upper level just above the food court. The mall, which has more than 200 stores, was crowded with weekend shoppers; many took shelter after hearing the shots or seeing people fleeing.
Police, who were in the area on another case, responded to the emergency calls within two minutes and found all three bodies either in the store or just outside it.
Aguilar had a backpack filled with crude explosives, and authorities were initially concerned he had booby-trapped himself, McMahon said.
"These were homemade devices consisting of flash powder and household items, so they're not very sophisticated," McMahon said.
Overnight, police searched Aguilar's home where they found more ammunition, and seized computers and documents. Police believe Aguilar legally bought the shotgun himself last month in nearby Montgomery County.
McMahon said he could not yet give further information about Aguilar, including whether he worked or was a student.
Aguilar lived less than a mile away from Benlolo, the female victim, in a quiet middle-class neighborhood with tree-lined streets in College Park, which is home to the University of Maryland's flagship campus.
There was no answer at Aguilar's address. Neighbors said he lived there with his mother and possibly a sister, and that the family, who had only moved in within the last couple of years, kept to themselves.
Neighbor Megan O'Reilly said she interacted with them only a couple of times. "The house, when I visited, looked immaculately kept on the inside," she said. "They were not very engaging as neighbors." (Reporting by Alice Popovici; Writing By Jonathan Allen; Editing by Cynthia Johnston, Sophie Hares, Jonathan Oatis and Marguerita Choy)