On Saturday, a shooter shot and killed eight people and injured at least seven others at a crowded mall north of Dallas, according to authorities.

The gunman, who officials believe acted alone and whose motivation is unknown, was killed by a police officer after opening fire outside the Allen Premium Outlets mall in Allen, Texas, according to the city’s police chief, Brian Harvey, during a news conference.

At the same news conference, Allen Fire Chief Jon Boyd stated that his department transported at least nine individuals with gunshot wounds to surrounding hospitals.

Two of those people died at the hospital, Boyd said at a second press conference Saturday night. Three of the victims were in critical condition and four others were stable.

Medical City Healthcare, which runs 16 hospitals in the area, said in a statement that its trauma centers were treating eight of the wounded victims, who ranged in age from 5 to 61.

Collin County Judge Chris Hill, the top elected official in the county where Allen sits, praised police and other first responders at a press conference, but expressed deep anger with “those that would do evil in our community, in our backyard.”

Separately, police in the nearby city of Frisco, Texas, said they had evacuated the Stonebriar mall late Saturday after receiving reports of shots fired there. It was not yet clear if a shooting had actually taken place.