A one-year-old boy is in a critical condition after being stabbed at a home in west London.
A woman in her 30s was also found with less serious knife wounds at the property on Swinfield Close, Hounslow, on Monday evening.
Police and paramedics were called at about 19:00 BST and the victims were taken to hospital by air ambulance.
The Metropolitan Police said officers were looking for a man who lives at the address and is known to the pair.
Any one with any information is asked to contact officers.