It is authentically reported from the Prophet (peace be upon him) that he stated:
"Whoever, among you, sees something abominable should rectify it with his hand; and if he has not strength enough to do it, then he should do it with his tongue; and if he has not strength enough to do it, (even) then he should (abhor it) from his heart, and that is the least of Faith."
So you should consider the situation to see what manner suits you most. However, be careful of the consequences of your enjoining good and forbidding evil.In short,
you must forbid what you are sure is a bribe as long as this will not result in greater harm (troubles) or the like. (Part No. 23; Page No. 586) May Allah grant us success. May peace and blessings be upon our Prophet Muhammad, his family, and Companions.