No peace after no contact

I broke up with my partner because I felt very much emotionally abused by gaslighting, provoking and then going silent, weird communication and also just outright verbal outbursts of anger towards me.
I tried to end on a high note, told him with respect, that it was just not working like this, I even built him up verbally, after he pitied himself via text. I finally listened to my gut and blocked him all over and went no contact.

Obviously that is not sth he can deal with, because he left gifts, that I gave him in August for his bday in my mailbox. I felt weird, but I just tossed them away, like he could have done. Then now over a week later: another gift, that I gave him, back in my mailbox. This time with a very condescending, bitterly sarcastic note attached. I hope this doesn't continue because even though I see the tactic behind it, I find it upsetting. Has anyone of you experienced this? Or is there advice on how to deal with this? I won't respond but it is straight up annoying of him to use my mailbox as his emotional trash can. Fun fact: it wasn't mailed, he put it there himself, twice now, plus: he is a cop.

I'm sorry I don't think there is a lot I could offer with regard to this. From my perspective, perhaps the best thing to do may be to simply ignore what your ex is doing. I realize that's easy to say. But I, at least, can't think of anything you could do that wouldn't likely just make matters worse. What your ex is doing, it sounds like to me, is trying to get a "rise" out of you. And chances are a negative response would could be just as reinforcing as a positive one simply leading to more attempts on his part to get your attention.

I don't know if this will be of any help however here's a link to an article, from PC's archives, on the 3 "secrets" of outsmarting a narcissist:

3 Secrets to Outsmarting a Narcissist (By Not Trying to)

Thanks for the link Skeezks. Everything they lay out in that article is true, these individuals are relentless.

Yes, thank you so much! It really helped reading this and I guess to sum up the article : the only way to win with them is not to play. So I keep grey rock, no contact and really try to drop the thought, everytime I think of him. Maybe someone in a similar situation reads this at some point. So I will recommend someone else who helped me: Kris Godinez videos on youtube.

I also think the best course of action, or inaction, may be to ignore his antics.

Are you in the US? any sort of mail tampering including leaving stuff in your mail box is against the law. I would report all of these incidents. They seem petty now but it proves he is still obsessed with you. Things could easily escalate especially if you made it clear you dont want to hear from him again.