Answer :
A Group Of Civilians Trained To Fight In Emergencies Is Called A, Militia Reserves.
I believe the answer is : Militia reserves
The militia reserves do not have constant and regular training like the legitimate armed forces do. But, they are often given a brief training to help defend the countries in case additional troops are needed to defend an invasion. As soon as the invasion is over, they would be released from their military duty and can continue with their normal job.
