A dual UK-Iranian national has become the sixth person to be arrested in connection with the suspected RAF Fairford terror plot.
Counter Terrorism Policing (CTP) said the 27-year-old man was arrested in the borough of Westminster on Thursday on suspicion of preparation of terrorist acts.
Officers have also searched two properties in the area as part of the investigation.
CTP said a 26-year-old man, a UK national, has also been questioned under caution.
Five British nationals, all in their mid-20s, were arrested on suspicion of explosives offences and terrorism near the military site in Gloucestershire over the weekend before being bailed under investigation on Monday.
Senior CTP national co- ordinator Vicki Evans said: “The investigation into circumstances surrounding events in Gloucestershire is hugely complex, and our specialist teams are interrogating multiple lines of inquiry.
“As we’ve made clear, we’re looking at all possible angles – including possible foreign state involvement.
“I’d like to thank the public for their continued support and patience whilst we work through this investigation.”
RAF Fairford has been used in recent months by US bombers after former prime minister Sir Keir Starmer granted the US permission to use British bases for “defensive” strikes against Tehran during the Middle East war.
Counter-terror police have said a quantity of petrol but no explosive devices were found in the vans that sparked the security alert near the airbase.
After US President Donald Trump criticised the decision to release the suspects, the Prime Minister insisted the UK was working closely with US and that the authorities had the situation under “the strongest grip”.
Earlier on Thursday, Israeli Prime Minister Benjamin Netanyahu claimed Israel handed Britain intelligence about the suspected terror plot.
Mr Netanyahu said his country warned UK authorities about the “Iranian-sponsored attack” shortly before Britain’s announcement of a ban on trade with illegal Israeli settlements in the West Bank.
Andy Burnham has said there were “strong indications” Iran played a part in the incident near the Gloucestershire military base.
