British Prime Minister David Cameron has written to the mother of a British doctor who died in a Syrian jail, saying Damascus must answer for his "sickening" death, the family's lawyer revealed Sunday.
Syria claims Abbas Khan, who was arrested last year after travelling to Aleppo to treat wounded civilians, committed suicide. But a British minister said this week that he was "in effect murdered" by the regime.
Cameron accused the regime of subjecting Khan, a father of two, to "despicable treatment", but the doctor's family, who have criticised Britain's efforts to secure his release, called the letter "too little too late".
"Abbas's death is a sickening and appalling tragedy and it is right that the Syrian regime should answer for it," said Cameron's letter, according to a copy sent to AFP by Nabeel Sheikh, the family's lawyer.
"Their despicable treatment of him and refusal to engage with us... to enable us to support him is utterly unacceptable," he added.
The prime minister, whose first son died in 2009, said he understood that words could do little to ease Fatima Khan's pain in losing a child and paid tribute to her "courage and fortitude" during the 13 months of his detention.
"I cannot begin to imagine how devastating losing Abbas must be, especially at a time when it seemed as if the regime might finally release him," he continued.
"I hope that you can draw some comfort from the out pouring of support you have received, and that you have space and time to grieve for him, as well as celebrate, with pride, the fact that he dedicated so much of his life helping others, including some of the most vulnerable in the world."
The prime minister vowed to "press for those responsible to be held to account".
But Sara Khan, the dead man's sister, doubted he would be successful.
"Is he going to actually now manage to get some answers from the Syrians?" she asked, during a Sky News interview.
"Are they going to be able to answer why my brother was killed, how he was killed, by who he was killed?
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"A sympathising letter is not enough to justify someone's death. It is just too little too late."
The family has dismissed Syria's claim that he took his own life just days before he was due to be freed and handed over to a British lawmaker.
Outside pathologist to observe official autopsy
The body of the 32-year-old orthopaedic surgeon was flown back to London from Beirut on Sunday. An autopsy will be conducted to determine how he died.
Lawyer Sheikh said relatives were "relieved that his body has been repatriated" and that the body was being transferred to a coroner's court in east London, where tests would be carried out.
He told AFP that pathologists would be looking for signs of torture on the body.
"The family hopes that all relevant tests as deemed necessary are carried out so as to ensure the post-mortem is concluded without delay and the body laid to rest as soon as possible," Sheikh said, adding that the tests would begin late Sunday or on Monday.
The autopsy will be carried out by an interior ministry pathologist, but the family has asked a well-known pathologist, Nat Cary, to also "independently observe and participate" in the tests, Sheikh said.
Police are "actively involved given the circumstances surrounding Dr Khan's death are highly suspicious", the lawyer added.
Khan's body was escorted out of Syria on Saturday by the International Committee of the Red Cross and returned to family members waiting in Lebanon.
The doctor's brother, Shah Nawaz Khan, blasted Britain's handling of the case and suggested that British authorities -- like their Syrian counterparts -- were suspicious of the doctor because he was a Muslim of Indian origin.
"In Syria, he's been executed for being British -- and he's been let down by his own government for not being British enough," he told Sky News.
Syria had said Khan was detained for "unauthorised activities" and that he was found hanging in his cell.