Watched a video of Al White: The Story of a Marine Grunt in the First Battle of Khe Sanh (April 1967)

He talked about a race fight on a ship leaving Okinawa to Nam, he claims 12 were killed and many injured. I personally don't ever recall hearing about the incident, therefore reaching out to you.

His comments on race issues is around 12:39, the results of the riot around 14:31.