A mother was stabbed three times in front of her child in an unprovoked attack in south London.
The victim, 36, was pushing her child in a buggy when a man attacked her from behind in Downton Avenue, Streatham Hill, on Monday.
The knifeman did not speak to the victim before he stabbed her at about 17:20 GMT then ran off.
Police said the woman's injuries were not believed to be life-threatening. The child was not hurt.
Neighbours told the BBC they heard the woman screaming and came out to help.
A man first on the scene said the victim told him: "I've been mugged."
Two people said the wounds looked as if they were to the victim's face or head area.
It is understood the woman was on the phone to her husband at the time and that he arrived soon afterwards.
No-one has been arrested. The Met said the suspect was a black man, about 6ft tall and wearing dark clothing.
Officers have been examining CCTV footage and are appealing for witnesses.