An 11-year-old survived the violence and was in surgery, police said.
Kaepernick's former teammate, Eric Reid, expressed concern that the NFL arranged the workout primarily for publicity.
But they do need to do some work, new research finds, including sticking to medication and changing behaviors.
Colin Kaepernick and his team have announced that the time and location of his NFL workout have changed and that it will now be open for the media to attend. NBC News' Blayne Alexander has details from Atlanta.
Nathan Michael Newell, 19, forced his way into the customer's home and assaulted a 78-year-old man who answered the door.