Sahih Muslim Book 20, Hadith Number 4514.

Chapter : Acceptance of gifts on the part of state officers is forbidden.

It has been reported on the authority of ‘Adi b. ‘Amira al-Kindi who said: I heard the Messenger of Allah (may peace be upon him) say: Whoso from you is appointed by us to a position of authority and he conceals from us a needle or something smaller than that, it would be misappropriation (of public funds) and will (have to) produce it on the Day of Judgment. The narrator says: A dark-complexioned man from the Ansar stood up-I can visualise him still-and said: Messenger of Allah, take back from me your assignment. He said: What has happened to you? The man said: I have heard you say so and so. He said: I say that (even) now: Whoso from you is appointed by as to a position of authority, he should bring everything, big of small, and whatever he is given there-from he should take, and he should restrain himself from taking that which is forbidden.