Shahid Mohammed was arrested following a house fire which led to the deaths of eight members of the Chisti family in Birkby, Huddersfield in May 2002. But after beiing released on police bail he disappeared and has not been seen since.
Six month-old Najeebah Nawaz, Aneesa Nawaz, 2, Tayyaba Bootall, 3, Ateeqa Nawaz, 5, Rabiah Bootall, 10, Muhammed Ateeq-Ur-Rehman, 18, and Nafeesa Aziz, 35 and all died in the fire, and 54-year-old Zaib-U-Nisa died in hospital a week later.
An image has now been created using “age progression technology” showing what Mohammed could look like now.
It is being used as part of a “day of action” in which police are taking to the streets of Kirklees to renew their appeal for information about his whereaouts.
A £10,000 reward has been offered for information which leads to the arrest and conviction of Mohammed.
In July 2003, three other men, Shaied Iqbal, Shakiel Shazad Amir, and Nazar Hussain, all from Huddersfield - were convicted for their parts in the crime. Nazar Hussain has since been released on parole.
Det Supt Lisa Griffin of West Yorkshire Police said: “It’s essential we find Shahid Mohammed, not only to bring him to justice but also to provide some closure for the Chisti family.
“For more than a decade now they have had to live with losing their loved ones in such a horrific way and knowing that not every person connected with the fire has been brought to account.
“Using the age progression process we have been able to create an image of what Shahid Mohammed could look like now and we are asking if people have seen this man or who may know his whereabouts to get in touch.
“My investigation team with the support of local NPT Officers are spending time in local communities across Kirklees reminding people what happened during the early hours of 12 May 2002 in an attempt trace and locate Shahid Mohammed.
“Since the fire the family have remained dignified but have had to allow their lives to carry on despite knowing so many lives were cut short, babies should have grown up to be children, children into teenagers and teenagers into adults.
“The investigation that followed the blaze became the largest multiple murder investigation that West Yorkshire Police had handled in nearly 30 years and we remain as determined as ever to trace Shahid Mohammed.”
Police and Crime Commissioner for West Yorkshire Mark Burns Williamson said: “Shahid Mohammed has been on the run now for more than ten years prolonging the agony of the Chisti family.
“Detectives have been hunting for him since his disappearance and believe the local community holds the key to finding him which makes the action of officers today essential.
“I would urge people to look at the age progression photo and speak to the police if they have seen Shahid Mohammed or who may know where he is.”
Anyone with information about Shahid Mohammed is asked to call 01274 373737 or Crimestoppers anonymously on 0800 555 111.