Five British nationals were arrested near RAF Fairford in England on suspected explosives and terrorism offences. Here is what we know so far.

The arrests: early on September 27, after a local farmer reported three suspicious white vans heading towards the base, armed police detained five Londoners in their early twenties. The vans contained no viable explosives, according to a source cited by Reuters.

Released on bail: all five were released on strict bail on September 28, but counter-terrorism police say the investigation continues and foreign-state involvement is among the lines of inquiry.

The claims: US Secretary of State Marco Rubio said on September 29 that the ‘hands of a foreign actor’ were involved, without giving evidence. President Trump said the incident ‘might be’ connected to Iran.

The denial: Iran’s London embassy categorically rejected any link, calling the speculation ‘unfounded and malicious’ and aimed at fuelling anti-Iran sentiment. RAF Fairford, in Gloucestershire, is a forward operating base for the US Air Force and has hosted American bombers during operations against Iran this year. British police say 85 homes near the base were evacuated as a precaution during the initial response.