A gunman wearing a pig mask has reportedly opened fire at a hotel in Las Vegas.
Guests and tourists have had to flee the city's famous Bellagio hotel on the strip.
Various American news sites have reported reported hotel guests dived under tables after the shooting began.
A picture of the shooter wearing a pig mask has surfaced on Twitter.
Reports suggest that the shooting is linked to an attempted armed robbery of a Rolex shop inside the hotel complex.
The Las Vegas Metropolitan Police Department has confirmed they are "currently investigating [a] burglary".
But they added in a statement: "Initial reports indicated there was an 'active shooter' which was false. NO injuries."
Panic ensued, with some holidaymakers and gamblers trampling over each other to escape the pandemonium.
Other reports claimed the robbers were also armed with sledge hammers, as well as firearms.