The teenage sister of a seven-year-old boy who died in an arson attack has been released from hospital.
Joel Urhie was found dead after the blaze at his family home in Deptford, south-east London, on Tuesday.
His mother, Sophie, and 19-year-old sister escaped by jumping out of a first-floor window and were taken to hospital with non-life threatening injuries.
Police said on Wednesday that Joel’s sister has been released from hospital, where her mother is still being treated.
Sources said one line of inquiry was the attack was gang-related amid reports Joel’s brother, Sam, 21, may have been the target.
Detective Chief Inspector Mark Wrigley said police are keeping an “open mind concerning motive” to the murder and that speculation about the incident “is not helpful”.
He appealed for anyone with information to come forward.
“This horrific incident has left a family shattered and the tragic loss of such a young life in suspicious circumstances resonates throughout the community in Deptford,” he said.
“Our sympathies are with Joel’s family and friends at this tragic time as they struggle to come to terms with their loss.
“I would directly appeal to anyone who was in the area and saw anything suspicious at around 3:30am, or who has any information about who was responsible for starting the fire that claimed to the life of an innocent child, to contact police immediately.”
CCTV footage which may hold vital clues to Joel’s murder was seized by detectives on Wednesday morning.
CID officers removed the box connected to the camera system from a flat on the other side of the road from Joel’s family home.
The camera does not point at the Urhie house but may have captured the person or people who started the blaze as they arrived at or left the scene.
Floral tributes have been left on the fence opposite the fire-ravaged house on Adolphus Street, where six fire engines and around 35 firefighters tackled the blaze after they were called at 3.25am on Tuesday.
Nearby properties were evacuated as a precaution and crews brought the fire under control just before 4.50am.