OMAHA, Neb. -- A man opened fire with a rifle at a busy department store Wednesday, killing eight people before taking his own life, in an attack that made holiday shoppers run screaming through a mall and barricade themselves in dressing rooms. Five more people were wounded, two critically.

The gunman left a suicide note that was found at his home by his mother, said a law enforcement official who spoke on condition of anonymity because he was not authorized to speak.

TV station KETV reported that the note said he wanted to "go out in style."

The shooter was identified as 20-year-old Robert A. Hawkins of Bellevue, according to friends and a law enforcement official who spoke on condition of anonymity because he was not authorized to speak publicly about it.

Witnesses said the gunman fired down on shoppers from a third-floor balcony of the Von Maur store.

He was found dead on the third floor with a self-inflicted gunshot wound, and his victims were discovered on the second and third floors, police said.

"My knees rocked. I didn't know what to do, so I just ran with everybody else," said Kevin Kleine, 29, who was shopping with her 4-year-old daughter at the Westroads Mall.

Sgt. Teresa Negron said the gunman killed eight people, then apparently killed himself. Authorities gave no motive for the attack and said they did not know whether he said anything during the rampage.

Police received a 911 call from someone inside the mall, and shots could be heard in the background, Negron said. By the time officers arrived six minutes later, the shooting was over, she said.

"Everybody was scared, and we didn't know what was going on," said Belene Esaw-Kagbara, 31, a Von Maur employee. "We didn't know what to do. I was praying that God protect us."