The suspected murder of a mother and her five children in a house fire is now being treated as a cold case, the BBC has learned.

Dr Sabah Usmani and her five children – Hira, 12, Sohaib, 11, Muneeb, nine, Rayyan, six, and Maheen, three – were killed by the blaze at their home in Harlow in October 2012.

Detectives say there are no longer any viable lines to investigate but will "continue to assess any new information".

The children's father Dr Abdul Shakoor, who was the only survivor that night, says he fears he will die before the case is solved.

Inquiries become cold cases when police believe a homicide has been fully investigated but remains unsolved.

It does not mean the case is closed but detectives will not actively pursue it day-to-day.

Shakoor has been told that unless new information surfaces, Essex Police will review the case in a decade's time.

"Who knows in 10 years whether I will be here," he told the BBC. "I don't know whether I'll be alive at that time."

He said the development from police was "very disappointing" news.

"I know that Essex Police have done a really great job and I still feel that they would like to resolve this case as a top priority. It is the matter of the six lives lost, all innocent. In one night, everything was taken away from me."

The family were asleep when the fire broke out in the early hours of 15 October 2012, quickly engulfing their home in Barn Mead.

Shakoor tried to raise the alarm to save his wife and children.

A neighbour's silver Ford Focus was set alight nearby at the same time.

Police launched Operation Shakespeare, but despite arrests, no-one has been charged.

In July 2025, an anonymous handwritten letter was posted to police in Harlow, weeks after a BBC podcast was broadcast examining the case.

Det Ch Insp Louise Metcalfe said it was "clearly" written by someone who wanted to progress the inquiry.

"They reference the 'nightmare' of having information but not feeling able to share it," she explained.

Metcalfe declined to share further details from the letter, but urged the author to come forward.

Shakoor, who is an endocrinologist, added: "I have a direct appeal to the author of the letter that you have made a very courageous first step.

"You came forward, and really, really, I feel it's my belief that you will come forward again.

"This is the really only thing which can help us resolve this case."

An Essex Police spokesperson said: "We remain determined to establish the truth about what happened and hold the person or people responsible to account.

"At this stage, unfortunately we do not have any viable lines of inquiry to actively pursue.

"Dr Shakoor knows we will continue to assess any new information which is provided to us."

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