Reading various reports seems to suggest to me its concrete decking or
supports thats failed rather than the steel structure. That might mean
no effect on the bridge or simple jacking respectively. However, that
a collection of eye witness non-expert reports.

Its nearly 6 hours afdter the event as a write this. Methinks
http://www.nationalrail.co.uk/servic...ons/today.html

by now ought to be saying something succinct than ''Train services
are being disrupted due to an operating incident in the London
Liverpool Street area. Services are currently unable to operate
between London Liverpool Street and Seven Sisters / Tottenham Hale /
Stratford. However, Chingford line services are running between
Chingford and Hackney Downs.''

Surely ''All services to/from Liverpool Street suspended'' as the
first sentence.

--
Nick