The High Court in Johannesburg concluded that Sandile Mantsoe stabbed Karabo Mokoena, and tried to conceal the crime by burning her remains.

Her killing sparked outrage with women using the hashtag #MenAreTrash.

South Africa has one of the world's highest rates of rape and murder of women.

More than 40,000 cases of rape are reported every year, figures which are thought to only represent a fraction of actual attacks.

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Presiding judge Peet Johnson labelled Mantsoe an unreliable witness who fabricated evidence and was involved in a web of lies in a bid to sway the murder trial his way.

How bad is gender-based violence in South Africa?

• The term "gender-based violence" refers to violence that targets groups or individuals on the basis of their gender.
• Almost a third of all women in the world who have been in a relationship have experienced physical or sexual violence by their intimate partner, according to the World Health Organization (WHO).
• Every four hours in 2016, a woman was killed in South Africa, and at least half of them were murdered by an intimate partner, according to fact-checking website Africa Check.
• In 2015, the global rate of femicide was 2.4 per 100,000 women. South Africa's rate was nearly four times the global figure, at 9.6 per 100,000 women.
• El Salvador, Jamaica and Guatemala have a higher femicide rate than South Africa, according to a 2011 study by the Small Arms Survey.

The 28-year-old denied killing Ms Mokoena but during his bail hearing, he claimed he had disposed of her body after coming home and finding that she had committed suicide by stabbing herself.

Her charred remains were found buried in a shallow grave in a deserted field in Johannesburg after her family filed a missing person's report in April last year.

She had been assaulted, doused with acid and then set alight.

Police said the accused had confessed to the murder as part of a ritual which would allow his business to prosper.

The family of the woman who was killed by Mantsoe has welcomed the guilty verdict, but have questioned his mental state because he showed no remorse during the trial, the BBC's Nomsa Maseko reports.

Speaking to reporters inside the courtroom, Mantsoe maintained his innocence saying the only thing he was guilty of was "trying to be a positive influence in her life".

South Africans are discussing the verdict on social media with the names of the victim and the killer the top trends on Twitter.

The judge's verdict comes a day after Zolile Khumalo, a female student from Durban's Mangosuthu University of Technology, was shot dead in her dormitory.

The male suspect, a 23-year-old graduate of the university, was arrested at the scene of the shooting.

Mantsoe is due to be sentenced on Thursday.