A two-year-old boy suffered a broken collarbone when his mother was assaulted at an east London train station in a racially motivated attack.
The 30-year-old woman had her son in a pushchair at Highams Park station when she was attacked by a man, who was black, after being racially abused during her train journey.
The victim, who is also black, was allegedly accused of having a mixed-race son by her attacker.
The toddler was injured after the man pulled the hair of the woman, dragging both her and the pushchair to the ground.
British Transport Police have released images of the man they want to talk to in connection with the incident on 23 June. They described the incident as an "unspeakable attack" on a mother and son.
DC Gerry Hughes said : "The victim, who had her two year-old son in a pushchair, was approached by a man at Walthamstow Central station.
"They both boarded the 2.47pm Liverpool Street to Chingford service. During the journey, the man began to racially abuse the victim.
"When the train arrived at Highams Park station, the victim left the train with her pushchair. She was assaulted by the man, who pulled her hair, dragging her to the ground along with the pushchair. The man then made off from the scene.
"The victim was shocked but uninjured. Her son was taken to hospital where he was diagnosed with a fractured collarbone. He was later discharged."
Anyone with information is asked to call freefone 0800 40 50 40 quoting background reference B9/LNA of 24/06/2013.
Information can also be passed to the independent charity Crimestoppers, anonymously, on 0800 555 111.