The ambulances were run by the Hatzola volunteer organisation, which provides free medical transportation and emergency response to those living in north London.
Nobody was physically hurt, but the police said they are treating the incident as “an anti-Semitic hate crime”.
While it has not been declared a terror offence, counter-terrorism officers are leading the investigation.
A little-known Islamist group with possible links to Iran has claimed responsibility.
The Harakat Ashab al-Yamin al-Islamiya (HAYI) group, meaning The Islamic Movement of the People of the Right Hand, has also claimed responsibility for similar attacks in Belgium and the Netherlands.
- Agence France-Presse