Four people were shot and killed, including an assailant, and at least three others were wounded on Sunday in two incidents, including one at a crowded shopping mall in Kansas City, police said.
Kansas City police were uncertain if the same man was involved at the two locations and were treating them as two separate incidents.
One person was killed in a house and two others were killed at the upscale Ward Parkway mall south of downtown Kansas City about 6 miles away, where police killed a gunman, according to Sgt Tony Sanders of the Kansas City police.
One of the wounded was a police officer who had responded to calls of the first shooting. His injuries were not life- threatening, police said.
"It was just mass chaos, as you can imagine on a Sunday in a crowded mall," Sanders said.
Police said the mall shooter used "a long gun" and would not clarify whether it was an assault rifle or shotgun.
The incident came almost two weeks after a Virginia Tech university student killed 32 people and then himself in the worst mass shooting in modern US history.
One eyewitness told CNN he heard three or four shots near the checkout aisles of a department store, and his son saw a man on the ground in shock with blood on his face.
The Kansas City Star said police were notified shortly before 4 pm CDT (1900 GMT) that a man was firing shots in the mall and that several people had been hit.
(Reporting by Carey Gillam in Kansas City and Jui Chakravorty in Detroit)