"I was crying out. I was screaming 'Reeva, Reeva'," he told the court. "I was overcome with terror and despair. At times I was screaming, at times I was crying out."
Chiziweni is said to have told police that he slept through the incident.
He was mentioned by name for the first time yesterday, just over two months after the start of the 27-year-old athlete's trial for the premeditated murder of his girlfriend.
Carice Viljoen, a friend of Pistorius whose father he rang moments after shooting 29-year-old Steenkamp, said when she arrived at the house, "Frank" was standing in the road with the estate security guards.
The housekeeper has been mentioned in several profiles of Pistorius written before the shooting. In one, in October 2011, he is described being asked by Pistorius, who addresses him as "brother", to bring him his prosthetic legs. In another he is referred to as a "live-in caretaker who keeps his home spotless".
A policeman who arrived an hour after the shooting confirmed that Chiziweni had been sleeping in a room off the kitchen and was awake when they arrived. He said the man spoke good English. "We said to him, 'You were here. What did you hear?"' the policeman said, adding that he had replied: "No, no, no, I didn't hear anything."
He said police had been unconvinced by his response: "We were all asking ourselves how he could not have heard anything," he said.
Barry Roux, Pistorius' barrister, said the defence would not be calling Chiziweni. "He says he was asleep."
Although Chiziweni was listed as a prosecution witness, a source for the state said it would not be calling him either, confirming that he told police in his statement he heard "absolutely nothing".Telegraph Group Ltd