Boyce was 30 and his girlfriend, Natalie Adepoju, was 27.

Police said it was not a criminal incident, and the coroner said they were waiting for toxicology results.

Boyce, 30, played Tyler in Twilight, the character who almost crashed his van into Bella before Edward stopped it with his bare hands.

Boyce's brother Chris Wayne wrote on Facebook: "I wish you were still here bro. The world lost an awesome person."

His mother Lisa Wayne wrote: "I'm sick without you. I'm torn, I'm lost. I'm in pain.

"I'd text you or call you when I was broken or worried about something, and you'd tell me, Ma, I got you, we'll get thru this together. Boy. Why did you leave me?"

She added: "Never another hug, kiss or to hear those words, I love you again. I'm broken. I love you Greggy, my Hunny."

She said Boyce and Adepoju were in the process of starting a chicken wings business with flavours named after west coast rappers.

'So much life to live'

Boyce leaves behind a 10-year-old daughter, while Adepoju had a young son.

A GoFundMe page for Adepoju's funeral said: "Natalie had so much life to live we are saddened that her life was cut short."

The Clark County Coroner's Office, which covers Las Vegas, confirmed the news to various US media outlets, telling USA Today the causes of death were pending toxicology results.

Police spokesman Larry Hadfield told the Las Vegas Review-Journal: "The incident was not criminal."