Two men have been detained after four ambulances belonging to the Jewish charity Hatzola were torched in north London.
The vehicles were set alight in Golders Green during the early hours of Monday, prompting a probe led by the Metropolitan Police’s counter-terrorism unit.
Officers arrested a 47-year-old in north-west London and a 45-year-old in central London on Wednesday morning.
Searches are under way at both addresses as enquiries continue.
Senior counter-terror commander Helen Flanagan said the arrests mark progress in the inquiry, but investigators have reviewed CCTV indicating that at least three people may have taken part.
She added that the police understand the community remains anxious and that investigators are working to identify and detain anyone else involved.
Detective Chief Superintendent Luke Williams outlined extra security steps, including officers posted to protect specific sites and more conspicuous armed patrols across the area.
He emphasised those measures are precautionary rather than a response to a fresh, specific threat.
The government supplied four replacement ambulances, which arrived at Hatzola on Tuesday to restore services while the investigation continues.
