Don't mess with Hilary Duff! The actress and protective mama of son Luca, 2, was involved in a scary paparazzi incident while in the park yesterday, March 17.  

Duff took to Twitter to share the unsettling news with her fans in a series of tweets, relaying the story and how she was in a position to actually have the photographers arrested, though she declined to do so.

In the tweets, Duff used the hashtag #NoKidsPolicy to refer to a law that she, Kristen Bell and other stars are trying to pass, which will prohibit paparazzi from taking pictures of celebrities' children. Duff has been a strong supporter of the law, and it's not hard to see why.

Though her trademark sweetness ultimately prevailed in this instance, we take her at her word when she says she'll be more assertive next time. Take note, paps!