UPDATE 6-Nine dead in Nebraska mall shooting

(Adds police comments)

OMAHA, Neb., Dec 5 (Reuters) - A 19-year-old man killed eight people and then himself with an assault rifle at a busy mall in Omaha on Wednesday, sending terrified workers and Christmas shoppers scrambling for cover.

"Now I will be famous," the gunman wrote in a suicide note, his landlady told CNN after finding a three-part document that she said included his will.

Police declined to discuss the contents of the note.

Five people were wounded, two of them critically, in the early afternoon rampage in the Midwestern U.S. city. Most of the victims at the upscale Westroads Mall were shot inside the Von Maur department store near the children's clothing area.

"It was horrible, just horrible," one woman told local television station KETV, saying she hid under a rack of clothes when the gunfire started.

The Nebraska shooting was the latest in a series of mass killings that have shocked the United States, where gun ownership is widespread and the right to bear arms is a fiercely contested constitutional issue.

The White House said it was a "terrible tragedy."

"It's hard to believe it would happen here," said Jennifer Bettger, who left the mall just before the gunman opened fire. "It stops you in your tracks. We're all asking why. Why here?"