Tulsi Gabbard's aunt, 78, is brutally stabbed to death and beaten with hammer 'by female author friend she mentored'

Potential Donald Trump running mate Tulsi Gabbard's aunt has been beaten and stabbed to death, allegedly by her protégé.

Caroline Sinaviana-Gabbard, 78, was found dead at the home of prominent Samoan author and playwright Papalii Sia Figiel, 57, on the Pacific Island.

Samoan Police Commissioner Auapaau Logoitino Filipo said Sinaviana-Gabbard was killed last Saturday and her alleged murderer turned herself in the next morning.

The pair, who were close friends, got into an argument at the home in the village of Vaivase-Uta – about a 10-minute drive from the Samoan capital Apia.

Potential Donald Trump running mate Tulsi Gabbard 's (pictured) aunt has been beaten and stabbed to death

Caroline Sinaviana-Gabbard, 78, was found dead in the village of Vaivase-Uta – about a 10-minute drive from the Samoan capital Apia

What sparked the fight was not yet known, but Figiel allegedly used a knife and a hammer to kill her - both of which were found at the scene.

Figiel then allegedly left the body lying in her house and driven about an hour to a friend's home in the village of Lotofaga and spent the night.

'It wasn't until Sunday morning while they were having breakfast that [Figiel] told her friend what had happened,' Auapaau said. 

Figiel soon after turned herself in to police in Apia and was arrested and charged with manslaughter, which was upgraded to murder after more evidence was found.

Sinaviana-Gabbard was herself a renowned author and poet, whose debut novel Where We Once Belonged was a bestseller.

She taught Pacific literature at the University of Hawaii for more than 20 years and was the first Samoan to become a full professor in the US.

After her retirement, Sinaviana-Gabbard returned to her native Samoa.

Prominent Samoan author and playwright Papalii Sia Figiel, 57, was charged with murder after a knife and hammer were found at the scene

Her brother, Tulsi Gabbard's father Mike Gabbard, is a state senator for Hawaii and mourned the death of his 'best friend'.

'She helped me considerably during my rebellious stage of adolescence. She got me hooked on reading,' he told Spectrum News.

'I love her deeply and wish her well as she continues her journey.' 

Senator Gabbard said he hoped his sister's killer 'will be punished to the full extent of the law'.

Tulsi Gabbard, a former congresswoman for Hawaii, had a short-lived campaign for president and is a potential running mate for Trump.