Sussex Police say Pisano was friends with Scottish man Michael Polding, whose body was found in his Brighton flat on July 16. They believe he died in May from a "blunt force trauma consistent with an assault".
Police spokeswoman Jill Pedersen said: "Ricardo Pisano also goes by the name Brandon Pillay, and also calls himself Ree or Ricky. Both his name and his age are uncertain.
"We believe he's in his 30s and we want to speak to him about the murder of 63-year-old Michael Polding, who was found dead in his flat in Brighton in July."
Pisano was from Cape Town, and had links to Croydon, Southampton and New Zealand.
Police were seeking him in the UK, but "it is possible that he may have left the country", Ms Pedersen said.
"We do not consider him a risk to the public."
The hunt for Pisano will feature on Britain's most successful crime-solving programme Crimewatch on Thursday. To coincide with the show, the man leading the investigation, Detective Chief Inspector Nick May, will make an appeal for help on YouTube.
He said: "We are making a nationwide appeal next week in an effort that someone will recognise Mr Pisano. He was a friend of Michael Polding and we are keen to speak to him about Michael's death."
He added: "We are still unclear as to when exactly Mr Polding died and our inquiries have shown that Mr Polding was friends with Mr Pisano. We think he may have information about Mr Polding's last movements."
It is unclear whether the New Zealand authorities will seek his extradition if he is caught by British police.
But a fellow escaper in August 2001 was recaptured in Australia in 2006 and extradited to New Zealand.
Last September, Taupo area commander Inspector Steve Bullock said police were still "actively" seeking Pisano and that a warrant for his arrest remained in place. He told a local paper: "Regardless of the level of crime and conviction, the escape of any prisoner is serious and warrants a serious police response."
Pisano is about 1.6m tall, of slim build and may have grown a beard. Police said he had known the victim for three to four years and they might have lived together at some point.
After Mr Polding's death, his family said: "Michael grew up with us in Scotland but found his younger years difficult due to his sexuality. In the 1970s he decided to move to London where he felt it would be easier to live as an openly gay man."
"Last year he decided to move to Brighton as he wanted to start a new life in the gay community in the city. Michael was a kind and caring man. Despite the distance between us he kept in close contact and we will miss him greatly."
Wanted
* Ricardo Pisano, also known as Brandon Victor Pillay.
* Wanted in connection with the death of Scottish man Michael Polding in Brighton in July.
* Escaped from Tongariro/Rangipo Prison in 2001.
* Originally from South Africa.
* About 1.6m tall, of slim build, in his 30s.
* Will feature on Britain's Crimewatch on Thursday.
