A member of the Muslim community leapt to the defence of Jewish diners after they were punched outside a restaurant in North London last month, police said.
The victims, two Jewish men in their late 30s and mid 40s, were followed by two suspects after leaving a restaurant in Baker Street at around 5.20pm on 23 May, the force said.
The suspects, two masked men in their late teens or early 20s, caught up with the pair at the junction with Melcombe Street and Glenworth Street and punched them.
They also “made remarks that have led police to treat this as a hate crime,” Scotland Yard said.
But a Muslim person swooped in and confronted the suspects, believed by police to be of Asian descent, and offered the victims shelter.
Police attended the scene and have since pursued enquiries but not managed to identify the suspects.
Detective Inspector Kevin Eade, of the Met's Central West BCU said: "This behaviour has no place in our city and it will not be tolerated.
"All Londoners should be able to live free from harassment or abuse. In this case two men from the Jewish community were assaulted, but it was the intervention of someone from another faith that helped stop the assault.
"This shows that people can help and support each other, not least by confronting those who would set community against community. If anyone has information about this or any other hate crime I would urge them to come forward."
Anyone with information is asked to contact police on 101 or via Twitter @MetCC, with the reference 5162/23MAY.