Muggers punched a two-year-old girl in the head as they demanded money from her mother, Scotland Yard said today.
The 23-year-old victim was shopping with her daughter in Wembley, north-west London, when two young women tried to rob her.
The attackers, thought to be in their teens, became aggressive and hit the mother on the arm before punching the toddler in the head.
None of the victim's belongings were taken, a Metropolitan Police spokeswoman said.
Detective Inspector Rebecca Reeves said: "Although the victim and her daughter do not have any visible injuries, this was a frightening experience for them."
A CCTV image of the two alleged attackers has been released after the attempted robbery which took place shortly before 5pm on Tuesday.
Both the women were of Mediterranean appearance, with long dark brown curly hair and aged 14 to 18.
One was around 5ft and was wearing a white jacket, black mini-skirt, tiger stripe leggings, black flat shoes and was carrying a large black fake leather bag.
The second wore a black jacket, blue denim "skinny" jeans, black Ugg-style boots and had a large brown fake leather bag with gold details.
Police urged anyone with information on the attack to call the incident room on 07917 067 281 or contact Crimestoppers anonymously on 0800 555 111.