A three-year-old boy was strangled and his mother stabbed up to two weeks before their bodies were found, police have said.
Detectives investigating the deaths of toddler Kailash Kuha Raj and 36-year-old Poorna Kaameshwari Sivaraj are appealing for anyone with information about what happened in their final days to come forward.
It is believed they were murdered by father and husband Kuha Raj Sithamparanathan, 42, who stabbed himself to death when police arrived at the family home in Brentford, west London on October 6.
Officers forced entry into the flat in Golden Mile House on Clayponds Lane shortly before 1am and found the devastating scene.
On Monday the Metropolitan Police said that post-mortem examinations found that Kailash died from compression to the neck, and both his parents from knife wounds.
The little boy was last seen on around September 24, and his mother three days earlier.
Detective Chief Inspector Simon Harding said: “My investigation remains ongoing and I would continue to appeal to anyone who may have information that will assist us to come forward.
“We now know how this family tragically lost their lives, but we still need to find out why.
“Our initial inquiries established that Poorna and Kailash had not been seen or heard from for some time; Poorna since around Monday September 21 and Kailash since around Thursday September 24. What happened between then and when our colleagues found them?
“Did you see any of the family, or hear from them, over this period of time? Any piece of information could prove vital.”
Anyone with information can call police on 020 8721 4205 or via 101 quoting CAD 7365/04Oct, or to remain anonymous contact Crimestoppers on 0800 555 111 or online.
The case has been referred to watchdog the Independent Office for Police Conduct because Mr Sithamparanathan fatally injured himself when officers entered his home.
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