Three people died in a shooting at a large shopping center outside of Baltimore, Maryland on Saturday, and police asked people inside the mall to stay in place while it was searched.
One of the dead at the Mall in Columbia, Maryland – apparently the shooter himself, was found near a gun and ammunition.
The person's identity was unknown, police said.
The sprawling shopping center with about 200 stores is located about 30 miles (48 km) north of Washington D.C.
Police helicopter landing at mall area, Saturday
News reports said that the mall, located about 45 minutes outside Washington, was on "lockdown" because of an "active shooter situation."
Howard County Fire and Rescue tweeted they were en route to the scene, and urged local residents to "avoid area."
The mall of about 200 stores in Howard County, Maryland, is a popular weekend destination for families and young children for its indoor carousel and play area.
The Baltimore Sun newspaper said shoppers reported hearing gunfire
before fleeing the upscale mall, home to several department stores such as Lord & Taylor, Macy's and Nordstrom.
NBC television spoke to one man who said he was in phone contact with his daughter, who was taking shelter in a Bank of America inside the shopping center, along with dozens of others.
The young woman described a chaotic scene as shoppers were told to evacuate or quickly take shelter.
"People were panicking," the man said.
AFP contributed to this report