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Them's fighting words!

They fought when they were a couple — so it seems pretty in keeping with the nature of their relationship that Chris Brown and Karrueche Tran are fighting now that aren't a couple. The dueling exes took to Instagram on March 11 and both went straight for the jugular.

Brown took jabs at Tran's foray into singing when he wrote in an Instagram caption (that he has since deleted), "I wish u the most successful career ever. But I promise you this, once this 'TALENT' you have starts to simmer, so will everyone else including [Manager] Jacob [York], all of your famous friends know u how? How? How? How? How? .. Ok. So to end this petty game that's gonna allow u to book more club appearances and 'MOVIES' that go straight to DVD I'll leave you this [heart emoji]!"

Tran quickly fought back via social media and referenced Brown's new remix of his song, "Back to Sleep," in which he randomly says her name in the song.

Tran bit back with an expletive-filled post, "You're calling me a b*tch yet you're screaming my name in a song about getting back together?"

The petite personality continued, "CAN ALL THIS PETTY S—T STOP. IT IS SO UNNECESSARY. You have a beautiful daughter and so much to live for. LIVE YOUR LIFE and be positive. I am so over the drama! I just wanna work and be happy and take care of my family. Every f—king day it's something new!!! And all you f—ks get your life and laughs from this s—t show.. I am MUHF—KIN' tied!!"

We'd say these two should just kiss and make up -- but that's the absolute last thing we think they should do!

Brown and Tran were together on and off for four years until finally splitting for good (or so they say!) in March 2015.

The turbulent exes have been known to air their grievances about each other publicly and on social media. The final nail in their relationship coffin appears to have been when Tran found out that the felon had a secret child, a daughter named Royalty, with another woman during the time they were dating.

At the time the news hit, Tran tweeted that she was done. Listen. One can only take so much. The best of luck to Chris and his family. No baby drama for me," she said."

Tran may not be into baby drama -- but it appears she's still into Instagram drama!