[UPDATE] Police Confirm At Least 50 Dead And Over 200 Injured In Vegas Festival Shooting

Hospitals have reported multiple causalities after a gunman allegedly opened fire on a crowd at the Route 91 Harvest festival in Las Vegas.

Footage posted to Twitter shows country music fans hitting the ground as a round of bullets can be heard in the vicinity.

University Medical Center in Las Vegas has confirmed multiple victims have been admitted with gunshot wounds.

There are also unconfirmed reports that the festival was just one of multiple locations targeted by the gunman.

The festival is headed by big country names such as Big & Rich, Jason Aldean and Jake Owen.

Owen tweeted that he had "witnessed the most unimaginable event tonight" and reassured fans that he was okay, but others weren't. 

[UPDATE 5.57pm AEST] BBC is now reporting at least two deaths and 24 injured.

[UPDATE 6.08pm AEST] Vegas police have taken 'down' one suspect, as reported by The Associated Press.

[UPDATE 7.32pm AEST] Aldean, who was performing on stage at the time the shooting began has issued a statement. He wrote on Instagram: "Tonight has been beyond horrific. I still dont know what to say but wanted to let everyone know that Me and my Crew are safe. My Thoughts and prayers go out to everyone involved tonight. It hurts my heart that this would happen to anyone who was just coming out to enjoy what should have been a fun night."

[UPDATE 7.38pm AEST] Joseph Lombardo, the sheriff of the Las Vegas Metropolitan police department, has told media that "twenty-plus" people have been killed. Over one hundred people have been injured and police officers are amongst those shot. He has also stated that "the primary aggressor" is dead but police are searching for his female companion. He also confirmed reports that the shooter had fired at the festival from the 32nd floor of The Mandalay Hotel.

[UPDATE 9.51pm AEST] Sheriff Lombardo has again spoken to media, now confirming at least 50 dead in the shooting and over 200 injured. CNN are calling it the "deadliest mass shooting in US history".