A South African judge sentenced four men convicted of murdering a Cape Town lesbian to 18 years in prison Wednesday, six years after her killing cast a spotlight on homophobic crimes.

The four men were convicted in October of stoning, kicking and stabbing to death Zoliswa Nkonyana just metres (yards) from her home in 2006. The 19-year-old had lived openly as a lesbian.

Prosecutors welcomed the sentence and said it sent a message that hate crimes would not be tolerated in South Africa, where violence against gays is common despite a liberal constitution, the only in Africa to allow same-sex marriage.

"We are happy that the court agreed with us that these gentlemen did not show any remorse and had a slim chance of being rehabilitated," National Prosecuting Authority spokesman Eric Ntabazalila told the Sapa news agency.

Lesbians in South Africa are commonly targeted for attacks known as "corrective rape" by men trying to "cure" their homosexuality.

Three years ago a man was sentenced to life in prison and another to 32 years for the gang rape, robbery and murder of Eudy Simelane, a lesbian activist who had been a midfielder on the national football team.

In December, Human Rights Watch issued a report accusing South Africa of "desperately failing lesbian and transgender people" by not doing enough to stop attacks against them.