A 20-year-old and a teenager are fighting for their lives -- after a shooting at a local casino. Just before 12:45 this morning, patrol officers were called to the third level of the Eldorado Casino parking garage. There, they found 20-year-old Ryan Caldwell and his brother, who's a juvenile, each suffering from at least one gunshot wound to the upper body. Both were taken to LSU Hospital with life-threatening wounds. Investigators believe they've identified the man responsible. He surrendered to investigators, and detectives seized the gun they think was used in the shootings. After interviews with the alleged shooter and other witnesses, detectives believe at this point that the man may have acted in self-defense. He's not been charged, and detectives are working with the Caddo Parish District Attorney's Office as the investigation continues.