Police have been alerted after a swastika was found carved into a pavement in Stamford Hill.
Shomrim, the Jewish neighbourhood watch group, contacted officers after the Nazi symbol was discovered close to a synagogue.
Witnesses have been urged to call the police with information.
Over the past week, a spate of swastikas printed on posters have appeared in a children’s playground in Stamford Hill.
Shomrim said it was "the first co-ordinated and repetitive act of antisemitism the area has ever seen".
Shulem Stern, spokesman for the group, said: "There is a sense of anxiety and fear amongst parents. This is the first targeted and repetitive act we have had to deal with. Normally it is isolated incidents, but this is no longer isolated. It is really unpleasant."
It is not know whether the playground swastikas and this latest incident are connected.
