The British Army could take up to two years to get back to normal after stepping in to cover the shortfall in Olympic security.
Speaking to The Guardian the military's chief planner for London 2012 said 18,000 troops were deployed - many at short notice and diverted from their usual duties.
Wing Commander Peter Daulby also warned that reducing the size of the military could put Britain at risk of not coping with civil emergencies.
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Medical staff who helped during the Westminster terror attack have received a royal thanks for their life-saving efforts.
Colin Gregg, the son of the founder of the Greggs bakers chain, has been jailed at Newcastle Crown Court for 13 and a half years.
Khalid Masood was killed by a single gunshot to his chest, after the terror attack which claimed the lives of four people, an inquest heard.