Further correspondence with TFL:

See my supplementary question below.

I still haven't heard from you on this. There is a widespread suspicion among users of the Northern Line and others that contrary to the official statements, a warning of some kind might have been received, and that this could have been the reason for the problems before the bombs.

Can you give a more specific reply to my question which would go some way to ruling out such a suggestion? What I am looking for is the specific times that particular parts of the network were suspended on the morning of 7th July, together with the exact reasons.

I got a reply with the same press release as before, but with the following addition:

Notes to editor

King's Cross St. Pancras is served by six Underground lines: Circle, Hammersmith & City, Metropolitan, Northern, Piccadilly and Victoria lines and is the Tube's busiest station with 84 million passengers travelling through it each year.

Bakerloo line - suspended between Paddington and Elephant and Castle in both directions from 08:07 due to a defective train in Piccadilly Circus northbound platform. Services resumed with severe delays.

Northern - suspended between Morden and Stockwell from 06:29 due to a defective train at Balham.

Piccadilly - suspended between King's Cross St Pancras and Arnos Grove from 07:57 to 08:28 due to a defective train at Caledonian Road.

It has been suggested in news reports that the reason for the bus explosion was that Hasib Hussain wanted to get onto the Northern Line at King's Cross, but could not, because the service was suspended. So possibly this list is incomplete. I've also heard that Oval station was closed.