Cape Town - Three family members have been killed in their home on a private golf estate in Stellenbosch on Tuesday morning, Western Cape police said.It is believed the father, 54, mother, 55, and 22-year-old son were attacked in their home in the De Zalze Golf Estate in the early hours of the morning, Lieutenant Colonel Andre Traut said.News24 spoke to Lieutenant Colonel Traut who confirmed two siblings, a daughter of 16 and a son of 20, were injured and admitted to a nearby hospital.The injured daughter has since been taken to Stellenbosch Mediclinic, and is in a critical condition, Eikestadnuus reported on Tuesday. She will later be transported to Vergelegen Mediclinic in Somerset West.Lieutenant Colonel Traut, though, would not disclose how the family was killed, or a possible motive for the murders."We are not speculating at this stage. The forensic guys are still on the scene," he said.No arrests had been made.Eyewitness News, though, tweeted that a man in his twenties had been taken in for questioning:#DeZalzeMurders A man in his early twenties has been taken in for questioning in connection with the gruesome murder. LI— EWN Reporter (@ewnreporter) January 27, 2015Twitter user Gregory Harington tweeted: "The scene outside 12 Goskestraat, De Zalze.""@Netwerk24Berig: @SamanthavdBerg1: Die toneel buite 12 Goskestraat, De Zalze. #DeZalzeMoord pic.twitter.com/lhtvUrXqSX" Murder in Stellenbosch— Gregory Harington (@AskGregory) January 27, 2015Eyewitness News tweeted an image of the front of the estate on Tuesday: Family attacked in Stellenbosch, leaving three dead http://t.co/iTqWb495Rz pic.twitter.com/LwgL86FkuJ— Eyewitness News (@ewnupdates) January 27, 2015 here.