An investigation is under way into an arson attack on four ambulances belonging to a Jewish charity in north London. Efforts are being made to verify a claim of responsibility by a group known as Harakat Ashab al-Yamin al-Islamia (HAYI). Security sources have cautioned against a rush to tie Iran to arson and it has not so far been designated as a terrorist incident. Nosheen Iqbal speaks to chief reporter Daniel Boffey – watch on YouTube. Help support our independent journalism at <a href="https://www.theguardian.com/infocus">theguardian.com/infocus</a>