1ºNo one is obligated to stay in India but if someone choose to remain,he/she should follow Indian law or else they are free to get lost from India.
Any student going to school is abide by school regulations within it's premises.once out of school the are free to live as per their choice.
It's a move simply to establish school discipline.till 1 month back everyone was living in a peaceful atmosphere within school and outside but thanks to some political parties who are using students for spreading unrest to creat a hostile environment in india.i am sure that the govt of India is capable to handle the situation peacefully and firmly.

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