Police are appealing for information regarding the assault of a 30-year-old woman carrying her pushchair, which left her two-year-old with a fractured collarbone at Highams Park station.
Detective Constable Gerry Hughes from the British Transport Police 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 as the train arrived at Walthamstow Central around 3.03pm. 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.
More top news
The threat level has been raised to critical by MI5's Counter-Terrorism Analysis Centre.
Sam Allardyce has quit as manager of Crystal Palace and retired from football management.
Authorities named Salman Abedi as the suspected attacker who detonated a bomb at the Manchester Arena.