Authorities are hunting for suspects after shooting broke out during a massive marijuana celebration in Denver, leaving two people with gunshot wounds.
The gunfire scattered thousands attending Saturday's 4/20 counterculture holiday, the first since Colorado legalized marijuana.
A man and a woman each suffered non-life threatening gunshot wounds, officials said. Local media reports said a third person was grazed.
Denver Police spokesman Sonny Jackson said investigators are looking for one or two suspects, asking festival attendees for possible photo or video of the shootings.
He said police had no motive for the gunfire.
Witnesses described a scene in which a jovial atmosphere quickly turned to one of panic at the downtown Civic Center Park just before 5 p.m. Several thought firecrackers were being set off, then a man fell bleeding, his dog also shot.
The annual pot celebration this year was expected to draw as many as 80,000 people after recent laws in Colorado and Washington made marijuana legal for recreational use.
Rapper Lil' Flip was performing when the shootings occurred.