"After I saw the photograph [of Rihanna], that wasn't funny anymore," 50 told MTV News on Tuesday, referring to a recently leaked image that depicted the bruised singer shortly after she was allegedly hit and bitten by Brown.
The rapper previously made mention of the alleged incident in his "Pimpin' Curly" and "Saturday Cartoons" videos on his Web site.
"I didn't have any information on it," he said. "You're just going on what the public actually had. It shifts the whole thing. Even if you're saying you're in a dysfunctional relationship, I understand that. There's a point when you're already past a woman fighting you back. You look at [the picture], and it's obviously past that point.
"There's some issues there that definitely gotta be addressed. Not to take any shots at Chris or Rihanna or take sides in any way, [but] it's really not cool," he added. "It's not funny anymore, so there will definitely be no more reference to that from me in any way."
Before seeing the photo, 50 said he had taken a lighter approach to the February 8 events.
"I thought that was something you could use for humor, like any other comedian would utilize current events to put into their actual [presentation], being humorous a little bit," he said.
Meanwhile, the Los Angeles Police Department is still investigating the source of the leaked photo, which first appeared on TMZ last week.
"They… were looking into it vigorously," an LAPD spokesman told E! Online on Tuesday.
According to E!, Brown is currently under investigation for a number of felony charges related to the alleged incident.