The gunman used a semi-automatic handgun to shoot and kill a woman, then walked to another aisle and shot and killed another woman, State Police Sgt Trent Smith said at a news conference early today.
One victim of the late last night shooting was an employee and the other was a shopper, he said.
The shooter was pointing his gun at a third person when police officers found him and shot and killed him, Smith said.
A large knife was found near the man's body.
"At this time, it appears that it's just random," he said.