I am residing in India. I want to know permissibility of working as Civil Servants in Non-Muslim Secular country like India. Can I apply for Foreign Service (one of the services offered in civil services)? Can you suggest to me some guidelines? In Foreign Service, extradition of criminals, protecting Indians (Muslim & non- Muslims) and their temples (all religions)in other countries, Passport service, Foreign relations etc. are involved.(2) Suggest what type of permissible employment for us in Non-Muslim Secular countries.

Praise be to Allah, the Lord of the Worlds; and may His blessings and peace be upon our Prophet Muhammad and upon all his Family and Companions.

As for Muslim's working for non-Muslims, states or individuals, we state the issue as follows:
1- A Muslim's perpetual working as a wage earner for a non-Muslim is Haram, since this state is a form of humiliation and disgrace, which a Muslim is required to avoid.
2- A Muslim's working for a non-Muslim to do some actions such as building a house, tailoring a dress or so on, is Halal since it does not incur humiliation or disgrace.
As for working in offices of extradition of the accused, there is no harm to do such a job if the accused person is oppressive; otherwise, it is Haram to extradite the oppressed person even though he is a disbeliever.
Then, if the accused person is a Muslim, it is Haram to extradite him to a non-Muslim government, whether he is unjust or wronged.
As for working on protecting non-Muslim's places of worship, it is completely Haram since it constitutes a form of co-operation in Shirk (Polytheism) and disbelief.
Then, one is allowed to work on passport offices as long as this does not cause any form of humiliation to you. Then, it is allowed to work there if there is nothing Haram. However, it is safer and better to avoid working for/with non-Muslim in general.
Allah knows best.