Detectives investigating the murders of a woman and her granddaughter in a fire in Greater Manchester have doubled the reward for information.
Hameeda Begum, 71, suffered 90% burns and died in the fire in Little Holme Walk, Bolton, on 23 June 2008.
Four-year-old Alana Mian died of multiple organ failure weeks later.
Anyone with information leading to the conviction of those responsible for starting the fire and killing the pair could now be paid £50,000.
The previous reward for information on the investigation, which has been running for more than two years, was £25,000.
Alana's mother Saima and firefighter Steve Morris were also seriously hurt in the fire, which began in a wheelie bin outside the house.
Det Ch Insp Jeff McMahon, of the Major Incident Team, said: "It is now more than two years since this terrible arson attack, which claimed of the lives of two totally innocent people and left a firefighter seriously injured.
"We remain determined to find those responsible for the double murder of both Hameeda and Alana, and the investigation will remain open until we have identified their killers and given the family some sense of justice.
"Fifty-thousand pounds is a life-changing amount of money so I would ask people to search their conscience and if they do have information that could help us convict these killers, please do the right thing and come forward and help us get justice for Hameeda and Alana.
"Hameeda and Alana's family deserve the truth and to know who was responsible for these awful murders."
Greater Manchester Police started a murder inquiry but have never charged anyone over the deaths.
Three people have been sentenced for witness intimidation in connection with the case.