This is Brozo the Creepy Clown, a television host on the Spanish language Televisa network. Apparently he gets very upset when people impersonate his co-host Marissa Rivera on Twitter. So upsetm in fact, that he threatens to come after them.
According to Boing Boing, the threatening part of Brozo's message translated to something along these lines:
We know about you. We're very close to you (we're on to you). Now you've really fucked yourself.