Simulated terror attack at Birmingham's ICC
15 August 2013 Last updated at 18:07 BST
A simulated terrorist attack involving 150 volunteers has taken place in Birmingham as part of a major European exercise.
The event has seen a "chemical" released inside the International Convention Centre.
Reactions will be analysed to help identify practices and procedures to improve emergency responses.
Chief Supt Chris McKeogh of West Midlands Police told BBC Midlands Today's Kevin Reide, these events are "extremely rare" but it is important be prepared.