Go to the police immediately. Do not hesitate for one moment. If you have evidence of his threats in the form of email, text messages etc. make sure they are saved. If you do not, don't let that stop you. Carrying out his threat is a serious criminal act and under new laws will be punishable by a €5,000 fine and/or 12 months in jail. So far he has not done it, but his threats constitute harassment. Do not be put off by the consequences. Let the police decide what to do. Don't allow yourself to be victimised by making any contact with your ex. Trying to cajole or negotiate with him will give him control and make things worse -- you will end up having to live with his threats or having the material publicised, both of which are bad outcomes. This is a matter for the law.