Sandile Mantsoe, accused of killing his girlfriend and burning her body, had dumped her a few weeks before she went missing.

This was said in the South Gauteng High Court in Johannesburg where Mantsoe, 27, is on trial for murder, assault with intent to do grievous bodily harm and defeating the ends of justice.

Karabo Mokoena, who was 22 years old at the time, disappeared on April 28. Her charred remains were found in a ditch a few days later.

Mantsoe pleaded not guilty to all charges.

In his plea explanation to murder, Mantsoe said through his lawyer, advocate Victor Simelane, that Mokoena had committed suicide.

Mokoena's friend of four years, Stephanie Leong, told the court that Mokoena had abused Mantsoe.

Leong started her testimony by telling the court about the day she went out to a Soweto club, Icon, with Mokoena on March 26, a day before her birthday.

"He came to our table. As soon as Karabo saw Sandile she got upset. Karabo was highly intoxicated... Sandile asked that I take her to his car because she was quite intoxicated," she said.

When the three of them left the club early in the morning, she said Mokoena and Mantsoe pushed each other around in the parking lot.

"The accused said to me he no longer wanted to be with Karabo and she was forcing [him] to be there. I said to them both, I was never involved in their relationship but from what I can see it's toxic."

A few days later Mokoena sent her photos of bruises on her eye and neck on WhatsApp while she was at Morningside clinic.

Leong said Mokoena went to Mantsoe's apartment after she was discharged.

Leong said she could not reach Mokoena on her phone from March 28 and "I kept asking the accused if he had seen Karabo and he said 'no'.

"At some point he said Karabo had secret hotels she would visit when she wanted to be alone. He said the name of the hotel but when I googled it, it was not in South Africa."

The trial continues.