A tangled web leads from Golders Green ambulance attack to Tehran

British investigators are circumspect, but experts and security officials say incident has hallmarks of Iranian intelligence

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From Golders Green, where four ambulances belonging to a Jewish charity were set alight in the early hours of Monday, a tangled trail likely leads across two continents to Tehran.

British investigators are circumspect. Speaking at an event on Monday evening, Sir Mark Rowley, the head of the Metropolitan police, described a very relevant and rolling threat" from Iran to the UK and specifically to Jewish targets but warned it was still too early" to attribute the attack in north London to Tehran.