text: The bodies of the ex-EastEnders star and her sons, Zachary and Amon, were found at the family home on Tuesday.
  Concerns about Ms Blake's welfare were passed to the Met police before it launched its missing persons inquiry.
  The IPCC promised it would conduct "a thorough investigation".
  A missing persons probe was launched on 16 December after officers attended the family's home in Erith.
  This was undertaken following information from the children's charity, the NSPCC, over concerns about Ms Blake's welfare, police said.
  Remains found in the garden of the family's home at Erith south-east London home were confirmed on Thursday as those of Sian Blake, 43, and her sons Zachary Bilal Kent-Blake, eight, and Amon Ben George Kent-Blake, four.
  A police spokesperson said they all died from head and neck injuries.
  Ms Blake's partner is being sought by police over the deaths.
  However, the BBC understands Arthur Simpson-Kent, 48, has left the UK and travelled to Ghana.
  Ms Blake and the couple's sons had not been seen since 13 December. They were reported missing three days later.
  The case is now being treated as a triple murder inquiry.
  Forensic specialists were later called in to search the family home and the bodies were found during excavations in the garden on Tuesday.
  Significant attempts had been made to conceal the bodies, police said.
  Det Supt Paul Monk, from the Met's Homicide and Major Crime Command, said the police were "continuing to appeal for any information about the movements of Arthur Simpson-Kent".
  Ava Blake, Ms Blake's sister, has claimed the former EastEnders star had previously said she wanted to leave her boyfriend.
  Sian Blake, who had motor neurone disease, played Frankie Pierre in the BBC One soap between 1996 and 1997.Probe into police after actress murder
  The Met referred its handling of the case to the IPCC earlier this week. It has now been confirmed the watchdog will proceed with an investigation.
  IPCC Associate Commissioner Tom Milsom said: "The loss of Sian and her two young boys, Zachary and Amon, is a tragedy and my thoughts are with their family during this very difficult time.
  "The IPCC will be conducting a thorough investigation into how police responded to the concerns for their welfare and their disappearance."
target: The Independent Police Complaints Commission is investigating the police response to concerns raised about the welfare of former actress Sian Blake and her two children.