Detectives in Cardiff are working with worldwide police agency Interpol to find the killer of a 22-year-old Somali man murdered two years ago.
Mohamed Musa died after an assault two years ago
Mohamed Musa died on 23 April, 2003, from injuries he suffered during a serious assault in Butetown, Cardiff, in the early hours of 18 April.
South Wales Police have named Mohamud Mahad, 20, who used the nicknames Mafia and Yabada, as their prime suspect.
A £5,000 reward has been offered for information which leads to an arrest.
Mr Musa had been socialising at a friend's flat in Angelina Street, Butetown, when a group of men arrived outside. He was then attacked.
Officers named Mr Mahad in connection with the murder shortly after Mr Musa died, saying they believed he had gone abroad.
He is described as being 6ft tall, of medium build, with brown eyes and hair - which was possibly cropped at the sides and longer on top - and a thin moustache.
He is Somali, but was born in Kenya, and may also be using the name Mahamoud Ahmed Hersi, as well as his nicknames.
Detective Chief Inspector Paul Bethell, who is leading the inquiry, said: "I would urge anyone with information as to the whereabouts of Mohamud Mahad to come forward, particularly the Somali community.
Mohamoud Mahad: The man detectives would like to speak to
"I offer my reassurance that all calls will be treated in the strictest confidence.
"We are working closely with Interpol who are assisting in our attempts to locate Mahad.
"I am confident we can find this man."
Mr Musa had a two-year-old son and was due to become a father for the second time around the time of his murder.
He had met his wife in Somalia, where she lives with the couple's children.
He had nine brother and sisters, had lived in Cardiff for 11 years and had been a pupil of Fitzalan High School.
In an appeal one year after Mr Musa's murder, his parents Musa Yusef and Noora Mohamed, said their lives had "stood still" since the day of the attack.
DCI Bethell added: "The family are still coming to terms with what has happened and South Wales Police remain determined to solve this case so that Mohamed's family can begin to piece their lives together again."
Anyone with any information is asked to contact the incident room between 9am and 5pm on 029 2052 7220, out of hours 029 2022 2111 extension 35310 , or Crimestoppers any time on 0800 555 111.