Police in Las Vegas have released dramatic body camera footage showing an officer shooting dead an armed suspect who had been choking his wife in front of his young daughter.

Police say they were called to the disturbance outside a convenience store early Saturday evening (11 November) and found the couple struggling over a 9mm handgun.

At one point police say the suspect, identified as 41-year-old Phillip Pitts, pointed the loaded gun at his head and threatened to shoot himself.

"Both subjects continued to struggle over the firearm, with the female telling Pitts, 'Don't do it'," Clark County Assistant Sheriff Tom Roberts said.

"The officer pulled out his firearm and told Pitts numerous times to put the gun down and step away.

"Pitts did not comply to any of the verbal commands. Officer Nesheiwat arrived shortly thereafter and saw that Pitts had a firearm pressed to the female's abdomen and also gave verbal commands for him to drop the gun."

In the video, one of the officers can be heard shouting "drop the gun" and "get away from her" as he calls for backup.

A second officer, David Nesheiwat, 33, then fires two rounds from his 9mm Glock handgun, striking Pitts, who falls to the ground but with his weapon still pointed at the woman.

The officer, an 11-year Las Vegas Metropolitan Police veteran, fired two more rounds at Pitts. The woman was also struck, and can be heard screaming in pain.

Roberts said both were taken to hospital. Pitts died having been shot in the arm and stomach, while the woman underwent surgery for a non life-threatening injury.

The incident happened at around 5.30pm in front of the Rhino minimart at 780 East Pyle Avenue, south Las Vegas.

The couple's 10-year-old daughter had been trying to keep Pitts away from her mother before police arrived, Roberts said.

Police say Pitts had no criminal history in Nevada but had been arrested for misdemeanors in Hawaii. His handgun was found containing eight rounds in the magazine, one round in the chamber and with the safety off, Roberts added.

Police said Pitts never fired his weapon and that the bullet that struck the woman had gone through Pitt's arm.

The shooting was the 21st this year involving Las Vegas Metro Police and the 10th fatal officer-involved shooting, the Las Vegas Sun reported. At the same time last year, police had investigated seven officer-involved shootings, three of them fatal.