Severe Specific Alert

"BRITAIN’S terrorist alert has been raised to its highest-ever level because the London rush-hour bombers are alive and planning another attack, The Times has learnt. Security services, military and police are on "severe specific" alert"

STATES OF ALERT

Imminent Precise intelligence of a planned attack with timing and location known

Severe specific Intelligence warning of a known terrorist plot

Severe general A high possibility of attack at some stage but without knowledge of the timing or target

Substantial Still a high alert but no intelligence of a specific plot