Twitty was shot and killed a week ago on Oakridge Avenue. His family said he was trying to break up a fight between some girls outside his home and was shot, officials said.
A witness said Twitty was not breaking up a fight but was cheering it on. The witness also said someone drove up wanting to know who hurt his niece and then left, police said.
Police said a short time later, a man walked up and started shooting. The witness said Twitty was not the target but was the one who was hit.
Police said Mitchell turned himself in to their custody around 8:30 p.m., he is currently in the Mongtomery County Jail.