A man has been arrested after a video showed a Tube passenger directing "horrific" anti-Semitic abuse at Jewish children.
The clip showed a man reading Bible passages to two boys in skullcaps and acting aggressively.
British Transport Police launched an appeal over the footage, recorded by a commuter on the London Underground.
The force said it had arrested a man in Birmingham on suspicion of a racially-aggravated offence.
Asma Shuweikh, who was widely praised for confronting the man in the video, said she "wouldn't hesitate to do it again" and wished more people had intervened in the altercation on Friday.
"If everyone did, I do not think it would have escalated in the way that it did," she said.
"Being a mother of two, I know what it's like to be in that situation and I would want someone to help if I was in that situation.
"When he started talking to the child I thought, 'no, I have to say something'. As a mother of two it's appalling, I can't sit back and watch that happen.
"To be honest I thought it is my duty as a mother, as a practising Muslim, as a citizen of this country, to have to say something.
"You can't just sit back and watch that because I felt that it was just getting out of hand. It was really getting too much."
Speaking to BBC Radio 5Live Ms Shuweikh said the response to her actions on social media had been "heart-warming".
"I can't take all the credit... I would not hesitate to do it again," she added.
"All my friends and family have been so supportive. But they're also worried about my safety because I have children back home.
"But when you're put in that situation you don't really think about yourself. You just think, 'look this is the right thing to do. I need to say something'."
Commuter Chris Atkins recorded the altercation on the Northern Line service before moving to swap seats with the young boy next to the man in the video.
"It was the children that really got me and everyone else, he was just screaming at these children. It was horrific in every sense," he said.