EIGHT men were arrested on Saturday in two separate counterterrorism police investigations.

Five, including four Iranian nationals, were arrested at locations in England on Saturday on suspicion of preparation of a terrorist act after a suspected plot “to target a single premises” was uncovered, London’s Metropolitan Police said.

The force confirmed a further three Iranian men were arrested as part of a separate operation.

Home Secretary Yvette Cooper said the arrests were sparked by “serious events that demonstrate the ongoing requirement to adapt our response to national security threats.”

The first four Iranians were arrested on suspicion of preparation of a terrorist act, contrary to section 5 of the Terrorism Act 2006; the fifth man, whose nationality is yet to be established, was detained under the Police & Criminal Evidence Act.

Those arrested include a 29-year-old man in the Swindon area, a 46-year-old man in west London, a 29-year-old man in the Stockport area, a 40-year-old man in the Rochdale area and a fifth man in the Manchester area. They remain in custody.