(2)The period specified in a notification issued under sub-section (1) in respect of any area shall not, in the first instance, exceed ninety days, but the Central Government may amend such notification to extend such period from time to time by any period not exceeding ninety days at any one time if, in the opinion of that Government, there continues to be in such area such disturbance of public peace and tranquillity as is referred to in sub-section (1) or imminent danger thereofand that for the prevention of offences involving the use of arms in such area it is necessary or expedient so to do.