A mother has spoken of her horror at being told her son might have been burned alive.
The scorched body of bus driver Kester David, of Russell Avenue, was found under a railway arch in Palmers Green in July 2010.
A post-mortem examination gave cause of death as burns and inhalation of fumes.
On the night of his death he was filmed at around 9pm buying petrol in a jerry can from Texaco in Lordship Lane.
Twenty minutes later he returned to his white Ford Transit van and filled it with fuel, but it broke down and the RAC were called out to repair it. His van was fixed by 11pm.
About four hours later, at 3.23am on Wednesday, 7 July, a black man was seen on CCTV entering the forecourt of the same Texaco, where he also purchased petrol in a jerry can.
Around 30 minutes later, a man wearing the same clothing and carrying a jerry can was seen walking north along Green Lanes, toward Bloomfield Lane.
Kester's family have watched the footage and say the man is not Kester.
At 4.20am a bright light was seen on CCTV coming from under the arches where Kester’s body was found. A number of people nearby heard screams at this time.
Kester’s mother, who is 80, said: "When the detectives informed me that the burnt body of a bus driver had been found, the one thing I hoped in my heart was that he was already dead when he was set alight.
“No mother should have to bury their child under such horrifying circumstances.”
Police say that the area where Kester's body was found is difficult to access and can only be reached by climbing over a metal fence and walking down a steep concrete embankment.
Detective Chief Inspector Noel McHugh, of the Specialist Crime and Operations Directorate, has now set out a number of things police are trying to establish, including the identity of the man on the CCTV and the whereabouts of Kester’s mobile phone.
On July 5, two days before Kester’s death, his phone was answered by an unknown man when called by a relative.
His phone, a Blackberry Curve, has never been found, but was used to make calls from Wood Green shopping centre and Whittington Hospital in the days after his death.
Two weeks after Kester’s death, police in Enfield received an email from someone calling themselves “Sharon”, who claimed to know who was responsible for Kester’s death. Police would like to hear from this person.
Kester, a bus driver with Arriva in Wood Green, was a keen DJ and fitness enthusiast.
For a period in early 2010 he worked for an internet radio station in Stoke Newington called Lynx Radio, using the name DJ Bain.
DCI McHugh, said: "Kester was a hard working, well-respected individual in his local community and I am committed to finding out why he died.
“Despite continued efforts to identify the circumstances surrounding Kester's death, it remains unexplained and we appeal to anyone who can assist with information to come forward.
“Kester's mother is now 80 years of age and one can only imagine the agony she has endured since July 2010 not knowing why her son died."
If you have any information about Kester David's death, please call the incident room on 020 8785 8099.