COLUMBIA, Md. -- Police in Columbia, Md., have identified Darion Marcus Aguilar, 19, as the suspect in Saturday's shooting at The Mall in Columbia.

Howard County Police Chief Bill McMahon said Aguilar, who lived in College Park, Md., fatally shot two people at a store before killing himself.

Police are trying to determine whether Aguilar knew either of the victims, who are identified as Brianna Benlolo, 21, of College Park, Md., and Tyler Johnson, 25, of Mt Airy, Md. Investigators have confirmed that Johnson had recently moved from Ellicott City.

"We have not been able to verify any type or relationship between him and our victims," McMahon said. "That is an open question."

McMahon said the shooter used a Mossberg 12-gauge shotgun that he legally bought in December to kill the two victims. Another victim was shot in the foot.

Aguilar arrived at the mall by cab around 10:15 am. Reports of shots came in an hour later.

Between six to eight shots were fired during the shooting, said McMahon.

Aguilar carried a backpack that had homemade explosive devices. He also carried a great deal of ammunition, said McMahon during a Sunday morning news conference.

The mall, which is now closed, is expected to reopen by Tuesday. There will be grief counselors on site there as Saturday shoppers come back on Sunday to pick up the belongings they left in the mall during the panic of the shooting.

When the mall reopens, there will be a "strong police presence."

Police are still working to find a motive for the shooting. "We still have a lot of work to do, a lot of interviews to do," said McMahon.

On Saturday, McMahon said the bodies were found in Zumiez, an apparel store catering to skaters, surfers and snowboarders, on the mall's upper level. Benlolo and Johnson were employees of the store, he said.

Saturday shoppers said they heard gunshots, setting off a scramble as they fled the mall or ran to hide.

Lauryn Stapleton, 18, who works at the Cartoon Cuts hair salon for children on the mall's second floor, said she witnessed the shooting near an escalator. She was getting food for her boss at the McDonald's, downstairs in the mall's food court, when she heard a loud sound from the level above.

"It sounded like somebody had dropped a brick off the top ledge and I heard someone say, 'Shots fired.' So I grabbed a kid and I looked — three people fell to the ground. I grabbed the kid and ran, had the mother follow me," Stapleton said.

"It was completely crazy — everybody started running and screaming" and Stapleton "almost passed out" from sheer hysteria, she said.

Tarah Lancaster-Williams and Tonya Broughton were at a mall spa for a "ladies' day out" when they saw people running.

"There was panic," Broughton said, flecks of the cream from her facial still on her face. "I mean, if you can imagine just hearing those words, 'There's a shooter,' no one really thinks twice when they hear those words. You really start to flee. So we fled to the nearest store — and even in there you didn't know if someone was coming in there."

Broughton said the two, who had been sitting next to each other in the salon, moments later lost track of each other.

"As much as you think you've seen this on the news forever and you think, 'Here's what I'm going to do, I'm going to go this way,' that all goes out the window," Broughton said.

They both ended up in the mall's Victoria's Secret store, where Broughton said managers locked store gates. "They were extremely comforting and kept us updated. They were calm, and we just hugged each other and tried to talk to each other."

Ed Main was shopping at the Justice store with son Noah, 15, daughter Tori, 12, and niece Ana Collins, 18, when they heard two loud pops. He said they were hustled by an employee into a storeroom in the back of the store. Main, from nearby Westminster, said the employee "shut the door and barricaded it from the inside."

It was more than an hour before they were able to exit the mall.

After the shooting, the Mall in Columbia sent out this statement on its Twitter feed: "Our hearts & prayers are with everyone in the Columbia community."

Columbia, with a population of about 100,000 people, was built in the 1960s as a planned community of 10 "villages." Columbia is about 18 miles from Baltimore and 24 miles from Washington, D.C.

Contributing: Greg Toppo and John Bacon