A gunman opened fire with a shotgun in a skate shop at a crowded shopping mall near Baltimore on Saturday (local time), killing two store employees and wounding another person before apparently killing himself, police said.
Howard County police said they did not know the motive for the shooting at the large mall in Columbia, Maryland, about 32 kilometres west of Baltimore.
Police identified the victims as Brianna Benlolo, 21, of College Park, Maryland, and Tyler Johnson, 25, of Ellicott City, Maryland. Both were employees of Zumiez, a skate shop where the shooting took place. The name of the gunman has not been released.
One person suffered a gunshot wound to the foot, and four others were injured in the chaos, police said. Howard County General Hospital said all five people had been treated and released.
The shooting happened at about 11:15 am 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 of whom sheltered in place after hearing the shots or seeing people fleeing.
Police said they found the body of the suspected gunman at the store and he had apparently committed suicide.
"He still had a large amount of ammunition on and about him and because of concerns about explosives and any other weapons he might have we are approaching this with an abundance of caution," Howard County Police Chief Bill McMahon told reporters.
Howard County Executive Ken Ulman said police arrived within two minutes of the 911 emergency call, but it took hours for the police to clear the building of shoppers and employees.
"This took a long time because you can imagine how many rooms there are in the mall. How many back offices, bathrooms and dressing rooms and nooks and crannies in the mall," Ulman told reporters.
McMahon said investigators were reviewing footage from surveillance cameras placed around the mall.
Colin Reddy, who works at the mall, told CNN he heard about eight or nine shots in all.
"We thought it was construction because there's a lot of construction going on at the mall right now. Then I heard it again. Like 'boom, boom, boom'. And then everybody started running," he said.
Reddy said he and the other employees closed the store's gate and waited in a back room for police to arrive.
Tonya Broughton of Silver Spring, Maryland, said she and a friend were getting facials when they noticed other shoppers running.
"It was panic. We just headed for the nearest store, Victoria's Secret," she said, adding that the store's employees herded everyone to the rear of the store.
"They were very nice, keeping us calm. They told us we were safe," she said.
Zumiez, which has more than 400 stores across the United States, said in a statement it was "deeply saddened by the violence" at its store. "Our hearts go out to the victims and their families." The company said it was arranging counseling for its employees in the area.
Police said the mall will remain closed for the evening.
The attack in Columbia follows a shooting 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 killing himself.
There also has been a spate of shootings in recent days at US schools and universities. A student was shot dead on Friday at South Carolina State University in Orangeburg, and at Purdue University in Indiana a teacher's assistant was shot and killed on Tuesday. In both incidents suspects have been charged with the crimes.