Five people have been arrested for the double murder at St John Stella Londt Retirement Centre in Sunridge last week.
One of those arrested is a 34-year-old carer who was working the night of the murders.
The other four are all men.
While the carer, and one of the men, were allegedly linked to the murder the other three were not directly linked to the attack but were alleged accessories to the murder.
None of the suspects are being named until they are charged in court and the investigation is complete, police said.
The arrests are part of the probe into the murder of Elaine Burns, 91, and Rose Langton, 87.
The two women’s bodies were found on their beds at the Sunridge Park centre.
They had been gagged and tied up.
Days later police discovered jewellery, wedding rings and Kruger rands were among the items stolen during the robbery and murder.
The arrests come after a week of intense interrogation and investigation by the Mount Road Cluster Trio Task Team led by head detective, Colonel Paul Orange.
Police spokesperson Colonel Priscilla Naidu said the breakthrough came after leads were followed from 10am on Thursday until Friday afternoon.
“After raiding the carers home, detectives followed up leads all through the day until this afternoon. In total five are arrested and more leads are being followed up to evaluate if there are more arrests to come,” she said.
The arrests happened between 1am and 2am to Friday.
The carer and her 30-year-old alleged accomplice are being charged with the murder while other three, aged between 22 and 30, are charged with conspiracy to commit murder and money laundering.
“Some of the stolen items have been located at one of the suspect’s homes in the Kuyga Informal Settlement in Port Elizabeth. Investigators are still working on the case and no other information will be released at this stage,” van Rensburg said.
All five suspects are due to appear in the Port Elizabeth Magistrates court on Monday.