Metropolitan Police officers visited the Essex home where a mother and her twin daughters were found dead just two days before their bodies were discovered.
Shighi Kotuvala, 37, and twin daughters Niya and Neha, who were 13, were found dead at their home in Grove Road, Chadwell Heath, on the evening of Monday, 11 May, but found no response or any signs of disturbance.
The bodies of the three females, which showed no signs of visible injuries, were then found at the home on Tuesday, May 12, before father Pullarkattil Kunjunny Rethish Kumar, 44, was found hanging in an area near a reservoir in Forest Road, Walthamstow.
The incident was referred to the Independent Police Complaints Commission on May 12.
An investigation was launched after police went to the home at 1.10pm on Tuesday, 12 May, in response to concerns about the welfare of the residents.
On arrival, officers forced entry and found the bodies of the females.
Officers were then called to to an area by a covered reservoir in Forest Road, Walthamstow, at 8:17am on Wednesday, 13 May, to reports of a 44-year-old man found hanging. He was pronounced dead at the scene.
The last confirmed sighting of the family was on Sunday, 10 May.
Post-mortem examinations of the bodies are due to commence today (Thursday, 14 May) at East Ham Mortuary.
Detective Superintendent Kenny McDonald, who is overseeing the investigation from the Homicide and Major Crime Command, said: "At this stage we are awaiting the outcome of the post-mortems to confirm cause of death, which will provide further evidence of what has taken place inside the house at Grove Road.
"However, at this stage in our ongoing investigation we are not looking for anyone else in connection with the deaths.
"We are making extensive enquiries to trace next of kin, who we believe to be outside of the UK."