Detectives investigating the murder of an elderly Italian couple who were found dead in the bedroom of their home in Wolverhampton have been granted extra time to question two men.
Police also said the house had been burgled and they believed a knife and hammer recovered from the scene had been used in the attack on Guiseppe Massaro, aged 80, and his 77-year-old wife Caterina.
Three men were arrested on Sunday night on suspicion of their murders. At a press conference on Tuesday, Superintendent Keith Wilson said magistrates in Birmingham had granted the force extra time to question two of the suspects.
He would not confirm which of the three men - two of those arrested are from Wolverhampton aged 32 and 21, while the third is a 30-year-old from Birmingham - the warrant referred to.
He also revealed that officers believed a knife and a hammer recovered at the scene in Woden Road, Wolverhampton, had been used in the "sustained and ferocious attack".
The couple were discovered dead by their granddaughter Lindsey Booth, 23, in the bedroom of their home on Friday evening.
Mr Wilson said results of a post-mortem examination are yet to be released but Mr Massaro had "defensive wounds" to parts of his body.
He told the press conference that officers were called to the house around 8pm and found the bodies of the couple, dressed in day clothes, in their bedroom. There was also evidence of a burglary, he said.
He said: "On arrival, officers found that the house had been ransacked and, in relation to the actual premises, we could see that a lot of property had been moved around the house."
He also said the couple's car, a black Peugeot 307 registration PK56 VRW, was stolen. It was later recovered from nearby Wednesfield. Two televisions were also taken in the incident, he said.
The couple's grandchildren, Miss Booth, Richard Booth, and Rosa Carella, were also at the press conference.
The family pleaded for anyone with any information to get in touch with officers and Mr Wilson said the force would particularly like to hear from anyone who might have been in the area around the time of the murders or who might have been offered the couple's car for sale.
Miss Booth said: "Our grandparents came to England in the 1960s to look for work and to create a better life for themselves.
"Since being in the country they did nothing but work hard in order to provide for their two daughters - our mothers - and, after becoming grandparents to seven grandchildren, this summer they were expected to become great grandparents to two twin girls, which is unfortunately no longer the case."
Miss Booth also said the family, both in England and in Italy, could not "even begin to grasp the evil that took apart in their house and how frightened they would have been".
* Anyone with information is asked to contact the Operation Stoke incident room on 0345 113 5000.