Two more people have been arrested by detectives investigating the murder of a toddler killed when a blaze tore through a flat.
Nineteen-month-old Siariah Letang died in hospital following the fire in Camberwell, south east London, early on Saturday.
Police have been given a further 24 hours to question a 27-year-old man and a 28-year-old woman arrested at an address in south London on Saturday night, Scotland Yard said.
A 19-year-old man and a 46-year-old woman were arrested in the Paddington area last night.
Fire crews used thermal imaging cameras and breathing apparatus as they attempted to rescue the child and four family members trapped in the building.
The group - reported to be grandmother Brenda Ricketts, 45, her daughters Shakira Jackson, 11, and Ellisha Letang, the child's 23-year-old mother, and her four-year-old son Cameron - were found with the toddler.
They were all unconscious and suffering from smoke inhalation.
Shakira remained in a critical condition today while the other surviving relatives were in a "serious but stable" condition.
The two-bedroom, first-floor flat in Arnould Avenue, a residential area of Camberwell, was destroyed by the fire which started in the early hours of the morning.
A post-mortem examination into the toddler's death yesterday gave cause of death as carbon monoxide poisoning due to smoke inhalation.
Anyone with information is asked to contact the incident room on 020 8721 4868, or Crimestoppers anonymously on 0800 555 111.Reuse content