Rihanna Tells Diane Sawyer What Happened With Chris Brown on '20/20' (VIDEO)

Rihanna tells Diane Sawyer on '20/20' that the fight between her and then-boyfriend Chris Brown last February was ignited by a text message he received on the night the violence between the two took place.

Rihanna alleges the text message came from a former girlfriend of Brown's. "I caught him in a lie and he wouldn't tell the truth, so I wouldn't drop it," she said. "It escalated into him being violent toward me."

Watch the video after the jump.Rihanna tells Diane Sawyer on '20/20' that the fight between she and then-boyfriend Chris Brown last February was ignited by a text message he received on the night the violence between the two took place.

Rihanna alleges the text message came from a former girlfriend of Brown's. "I caught him in a lie and he wouldn't tell the truth, so I wouldn't drop it," she said. "It escalated into him being violent toward me."

To Brown's fans who argue Rihanna must have done something to provoke him, she had this to say: "It's ignorance ... because even if i hit him first, that makes it okay for him to do that to me?" She calls such attempts to defend him an "excuse for what he did."

Watch the video from Daily Drama below.