JOHANNESBURG (Reuters) - A South African court jailed a white woman on Wednesday for yelling racist abuse at a black policeman, in a case that laid bare attitudes that endure more than two decades after the end of apartheid.

In a ruling that lawyers believed to be the first prison term imposed in South Africa for verbal racial abuse, estate agent Vicki Momberg was sentenced to three years, with one year suspended, for directing deeply offensive slurs at the officer.

Previously people convicted of the same crime have been fined.

A video clip went viral following the incident in 2016 when the policeman tried to help Momberg after thieves broke into her car at night at a shopping center.

It showed her saying she wanted to be helped by a white or ethnic Indian officer, and that black people were “plain and simple useless” and “they are clueless, clueless”.

In her rant, she several times called the policeman a “kaffir”, apartheid-era slang for a black person and one of the worst terms of hate speech in South Africa.

Momberg wiped away tears as judge Pravina Rugoonandan read the ruling in a Johannesburg court, finding her guilty on four counts. Momberg’s lawyer Kevin Lawlor said she will seek the right to appeal her sentence.

The episode highlighted how 24 years after Nelson Mandela became South Africa’s first black president, espousing reconciliation, it is still struggling with race relations.

Despite the emergence of a black middle class, income gaps remain clearly visible along race lines, fuelling perceptions of white privilege. Black people make up 80 percent of South Africa’s 54 million population, but most its wealth remains in the hands of whites, who account for about 8 percent.

Justice Minister Michael Masutha said the custodial sentence could “serve as a deterrent” to others. “It was a question of escalating and intensifying the fight against racism by finding even more sterner measures,” he told eNCA television.

Johannesburg-based criminal lawyer Zola Majavu, who was not involved in the case, said: “This case has been put on the spotlight, it may be the first time - at least that I’m aware of - that a person has been sentenced to jail without the option of a fine for such action.”

However, in October, two white farmers who had been filmed pushing a wailing black man into a coffin were sentenced to jail for attempted murder, assault and kidnapping.

In 2016, a court ordered Penny Sparrow, a white woman, to pay 150,000 rand ($9,941) to charity after she was found guilty of hate speech for referring to blacks as “monkeys” in a Facebook post.