A dad and daughter were found dead after the alarm was raised when the child failed to turn up at school.
Mark Gordon, 36, and Hope, 6, were discovered at their family home in West Calder on Monday afternoon.
Police confirmed they were called to the house after Hope was absent from primary school. Fire crews also attended to break the door down.
Their deaths are being treated as unexplained. A post mortem is due to take place.
Enquiries remain ongoing but detectives said there is nothing to suggest anyone else has been involved.
A team of officers from Police Scotland’s Major Investigation Team, plus the local division, are involved in the investigation.
Detective Chief Inspector Bob Williamson, of the Major Investigation Team, said: “Our thoughts remain with the man and girl’s relatives at this extremely difficult time and they continue to be supported by specialist officers.
“They are understandably devastated and it is vital we get answers for them.
“At this time, we have no information to suggest anyone else is involved and our enquiries are continuing.
“I would ask that anyone with any information, no matter how small or insignificant you think it is, gets in touch with officers.”
Police said they will continue to maintain a heavy presence in the community as the investigation continues.
A large cordon remains around a number of properties on the quiet residential street. A large forensic tent could be seen in the garden of the family home.
It is understood the family had recently moved into the street.
Yesterday neighbours told the Record they have been left devastated by the tragedy.
One neighbour, who didn’t want to be named, told the Record: “I saw firefighters trying to get in through the back door yesterday.
“I didn’t want to be nosey so I turned away. But within 30 minutes, police were everywhere.
“I knew something awful had happened.
“The wee girl was a lovely wee thing and very sweet.
“I didn’t know them personally but we’d see them in passing.
“You’d never expect this to happen a stone-throw away from your front door.”
Chief Inspector Elaine McArthur-Kerr, local area commander, said: “We understand the significant impact this will have on the local community and I would like to thank everyone for their help so far.
“This incident is very upsetting and worrying for the people living in this community and would ask anyone with any concerns to speak to us.
“A police presence will remain in the area while we carry out investigations and anyone with any concerns, or information, can approach these officers.”
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