Speak to your manager about it. Be prepared to speak to legal about it.
Not doing so - even if you don't do what they're asking - is possible grounds for disciplinary action if discovered later, e.g. these people are caught bribing others, their files are gone through, and your name pops up as somebody they approached and it's realised you kept quiet. At that point you may have damaged the trust your employer has in you.
Not doing so - even if you don't do what they're asking - is possible grounds for disciplinary action if discovered later, e.g. these people are caught bribing others, their files are gone through, and your name pops up as somebody they approached and it's realised you kept quiet. At that point you may have damaged the trust your employer has in you.