Three people including a three-year-old boy have died at a home in Brentford, west London.
The toddler and a woman aged in her 30s were found dead at a home in Clayponds Lane shortly before 1am on Tuesday, the Metropolitan Police said.
They also found a man, believed to be in his 40s, who had suffered stab injuries.
He was treated by paramedics but pronounced dead at the scene.
Police said the child and two adults were known to each other and they are not looking for anyone else in connection with the deaths.
They are working to inform relatives.
Anyone with information can call police on 101 quoting ref CAD 7365/6 Oct.