Seven people have been arrested over an alleged plan to commit an arson attack targeting the Jewish community, the Metropolitan Police has said.
The force added that the specific target or venue is not known.
Officers from Counter Terrorism Policing London arrested three men aged 24, 25 and 26 in Harpenden on Sunday. They were later released on police bail.
On Monday, a 25-year-old man was arrested in Stevenage, while a 26-year-old man and two women aged 50 and 59 were arrested in a car in Birmingham on Monday remain in custody at a London police station.
