Keef later tweeted that his account had been hacked.
In April, JoJo released "3hunna K," a track that he rapped "ain't a diss song, this is just a message" but found him riding Chief Keef's "Everyday" beat while guns appeared in the accompanying video.
The track was a response to Chief Keef affiliate Lil Durk's earlier rhymes about JoJo's Bricksquad crew, which JoJo followed up with an additional track on the subject. A shaky YouTube video uploaded on Tuesday pictures JoJo allegedly driving by Lil Reese -- another member of the Keef/Durk crew -- and engaging in a profanity-laced verbal argument. "I'ma kill you," the person claimed to be Reese clearly states in the video. According to the Tribune, police were investigating "whether the shooting was sparked by a gang conflict."
JoJo aimed a number of Twitter replies at Lil Reese on Tuesday, though the other MC didn't appear to respond.
Chicago has seen a number of homicides this summer, with 55 recorded in the month of August according to RedEye Chicago -- the most of the year so far.