An investigation has been launched by homicide detectives after two bodies were found in a house in Ruislip.
The Metropolitan Police said the bodies of a woman in her 30s and a seven-year-old boy were discovered on Wednesday December 14.
The emergency services were called following welfare concerns being raised for the occupants of the house in The Fairway.
A statement from the police said: "On Wednesday 14 December, at about 10.50am, officers forced entry to a house in The Fairway, Ruislip following welfare concerns being raised for the occupants.
"Inside officers found the bodies of a woman in her mid 30s and a seven-year-old boy.
"Police believe they know the identity of those concerned and are in the process of informing next of kin; formal identification awaits."
The Fairway, in south Ruislip, is a quiet residential street lined with detached and semi-detached homes with manicured gardens fronting tree-lined boulevards.
A post-mortem examination is scheduled to take place at Fulham Mortuary on Friday 16 December.
At this stage the deaths are being treated as unexplained.
Detectives from the Homicide and Major Crime Command are investigating.
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