The police are seeking 20-year-old Travis Murdoch for questioning in relation to the alleged murder of Greek national Kevin Kourtis last month.
Three teenagers aged 16, and two aged 17 have been charged with the murder of Kevin Kourtis, who was attacked when he opened his front door on Langton St, Riverstone, in the early hours of Sunday, May 24.
Read More: Greek man stabbed to death inside his Sydney home
The Greek man died from multiple stab wounds after five men allegedly stormed into his home. Two women, aged 34 and 43, were also at the Langton Street address when the alleged ambush occurred.
Paramedics were called to the home just after 12.30am, where they performed emergency treatment on the 39-year-old victim but he died a short time later.
Police released an image of Travis Murdoch on Thursday and are appealing to the public to report his whereabouts.
He allegedly fled the home in a silver 2008 Subaru Forrester with two others and police have not yet been able to locate him.
Police are still investigating whether Kourtis knew the boys and if it was a targeted attack.
Murdoch is described as an Aboriginal or Torres Strait Islander, between 170-180cm tall with a large build, short cropped black hair and a moustache.
Murdoch is known to frequent areas such as St Marys, Mt Druitt and Quakers Hill.
Anyone with information about this incident is urged to contact Crime Stoppers: 1800 333 000 or https://nsw.crimestoppers.com.au