Two Las Vegas police officers and a civilian have been killed in an apparent ambush that ended with the two gunmen killing themselves, media reports say.
One of the attackers yelled "This is the start of a revolution" before shooting the officers and stripping them of their weapons and ammunition, the Las Vegas Review-Journal said.
Las Vegas 'ambush' leaves 5 dead
Two police officers sitting down at pizza restaurant in Las Vegas are shot before two suspects and a civilian perish in a shoot-out in a Walmart store.
Two officers were shot by the gunmen - a man and a woman - as they ate lunch at CiCi's Pizza, it said, citing police sources.
One of the officers died at the scene and the other died in surgery.
The attackers then headed to a nearby Walmart store, exchanging gunfire with and ultimately killing a civilian who was carrying a concealed weapon.
The male shooter, described as a tall white man, yelled "everyone get out" before shooting, Assistant Sheriff Kevin McMahill said.
The two gunmen then went to the back of the Walmart for "some kind of suicide pact", he said.
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Five killed in Las Vegas shooting
RAW VISION: Police respond after two shooters kill three people, including two police officers, in Las Vegas before allegedly shooting themselves. No sound.