A shooting at a Walmart store in Colorado on Wednesday evening has resulted in multiple casualties, police said.
"Multiple parties down. Please stay away from the area," police in Thornton, north of Denver, said in their initial post on Twitter.
About an hour later they said it was "NOT an active shooter" situation.
One person was killed and another was wounded in the shooting, local television station KMGH reported, citing law enforcement sources.
A spokesman for the Thornton Police Department could not be immediately reached by AFP.
Last month, a gunman in Las Vegas killed 58 people in the country's worst mass shooting in recent history.