[UPDATE] UK prime minister says Iran's Revolutionary Guard almost certainly directed the RAF Fairford plot

London summoned Iran's ambassador, who denied involvement and asked for evidence; no suspect has been charged.

Andy Burnham (Prime Minister, UK) told Parliament on Monday, Oct. 12, that the Fairford plot was 'almost certainly' directed by Iran's IRGC, firming up his earlier 'strong indications' of an Iranian link (AP), and sanctioned two Iranians as 29 countries condemned the plotting.

PREVIOUSLY

Sept. 27 — A suspected plot targeted RAF Fairford, the U.S.-run English base used for bombing runs on Iran.
Sept. 30 — Police found petrol, not explosives, in three vans tied to five suspects, all freed on bail.
Oct. 2–4 — Police arrested a sixth suspect, a 27-year-old UK-Iranian national, then released him on bail too.
Oct. 4–5 — The Pentagon flew all 12 B-1 bombers home to the U.S. on Oct. 4; on Oct. 5 Rubio called it routine, then Trump said threats drove it.
Oct. 6 — U.S. officials told the WSJ Iran planned to hit the jets with drones and kill American pilots.
Oct. 7 — Police arrested a seventh suspect, a 22-year-old British man.

Where the case stands:

29 countries, including the U.S. and UK, signed the Monday, Oct. 12 joint statement condemning IRGC plotting (Axios).
Seven men in their 20s have been arrested; all are out on bail and none has been charged (Washington Examiner counts six).
Police found gasoline in three vans tied to the first suspects, but no explosives.