At least two people were killed and 24 were hospitalised after a shooting at a country music festival in Las Vegas, a local hospital spokeswoman said, and police said one suspect was down.
The spokeswoman for the University Medical Center hospital said 14 of the wounded were in a critical condition.
All had suffered gunshot wounds, she said.
Las Vegas Metropolitan Police Department said on Twitter:
“Confirming that one suspect is down. This is an active investigation. Again, please do not head down to the Strip at this time.”
It was not immediately clear whether the suspect was killed or injured. Officers were due to give more information shortly.
Police had earlier said they were investigating reports of an active shooter near the Mandalay Bay Casino.
The New York Times reported that the shooting appeared to be at a country music festival and that police were investigating reports of shooting at other venues on the city´s famous strip.
Police made no immediate comment about that on social media.
One Twitter user posted that the casino hotel was on lockdown, while another, citing police scanners, said two gunmen who had shot at a bodyguard and police were on the 32nd floor.
Video clips posted online showed what sounded like automatic weapons as panicked concertgoers fled, dropped to the ground screaming.
Witnesses heard numerous gunshots at the hotel, where police tactical teams were searching for the attacker, according to reports on CNN and in the New York Times.
Flights at Mccarran International Airport were temporarily halted after the reported shooting, the airport said on Twitter.