A Limpopo man was arrested on Tuesday after allegedly raping a 28-year-old mentally challenged woman. 

Police also arrested the victim's grandmother who, for the past three years, allegedly arranged for the victim to have sex with the man in a bid to impregnate her. 

The rape incident is said to have taken place in bushes in the Mokwakwaila policing area near Bolobedu, outside Tzaneen.  

"It is alleged that members of the community in a village within this area received a report that a middle-aged man was raping a 28-year-old mentally challenged woman in nearby bushes," said police spokesperson Col Moatshe Ngoepe.

"The community responded immediately and managed to catch the suspect."

Ngoepe said the community summoned police to the scene who arrested the two suspects.

"The preliminary police investigation reveals that the victim's grandmother had allegedly arranged with the suspect to sleep with the victim over the past three years so that she could have a child," he said.

In a separate incident, a 27-year-old mentally challenged woman was raped on Friday after walking from a church service to her home in Phalaborwa.

"She allegedly met an unknown man who asked her to accompany him to a certain house, where he raped her," said Ngoepe.

Police said no arrests had been made and they were seeking assistance to locate a middle-aged man believed to be the suspect. 

The provincial police expressed concern at continuous incidents of serious and violent crimes perpetrated against mentally challenged women.

Acting provincial police commissioner Maj-Gen Jan Scheepers encouraged members of the community to strengthen safety around people living with disabilities, especially women who were mentally challenged.