A grandmother died of shock after being held at gun point and forced to watch as her three terrified nieces were brutally raped in front of her.

The distraught 71-year-old woman was confronted by an intruder in a balaclava who broke into her home.

He locked the three sisters aged 19, 22 and 25 who live with their grandmother in her bedroom and dragged them out one at a time to rape them in the property at Impendle in South Africa.

Police investigating the shocking triple rape attack believe the trauma of helplessly having to witness each individual ordeal caused her heart to give out.

Family spokesperson Mzandwile Ndlovu said: “The suspect had locked the three girls in their grandmother’s room and he brought them out one-by-one and raped them.

“We found the grandmother in the house but she was already dead and we think that she was so horrified by what she saw in these evil acts that it caused a heart attack.

“The three girls said the suspect did not touch her or harm her so it must be so” he said.

South African police spokesperson Captain Nqobile Gwala said: “An unknown suspect wearing a balaclava forced his way into a home and raped three family members at gunpoint.

“A 71-year-old woman who witnessed the incident collapsed and died and we are appealing for anyone who may have information about the incident to contact the police” she said.