Lane Graves bent over to scoop wet sand into his small plastic bucket when the alligator struck.
The 2-year-old boy wanted to build a sandcastle on the beach at Disney's Grand Floridian Resort and Spa after stormy weather canceled a scheduled outdoor movie.
His father, who was standing nearby with his wife and 4-year-old daughter, heard a splash and turned to see the alligator grab Lane's head, according to Orange County Sheriff's Office reports released Monday.
Matt Graves jumped into the water, pulling on the gator's snout in an unsuccessful attempt to free his son from its grip.
Seconds later, the gator pulled Lane underwater and both disappeared into the Seven Seas Lagoon, the report states.
Detectives recently completed their investigation into the June 14 attack, ruling Lane's death an accident. The reports released Monday detail the terror the vacationing Nebraska family experienced and the horror hotel guests witnessed.
At least one witness lost consciousness after the attack, and deputies offered counseling services to another who remained distraught more than a day later, according to the report.
Matt Graves also went to Florida Hospital Celebration Health at the recommendation of emergency medical crews, who found he had multiple cuts on his hand from the alligator's teeth and scratches on his foot, the report states.
A lifeguard told deputies he heard screaming and saw Matt Graves with blood "all over the right side of his face and right hand," the report states.
The lifeguard said he then saw the victim and the alligator in the water 15 to 25 feet from shore. The gator started splashing around, the lifeguard told deputies, and then both went under as the gator dragged the boy farther into the lagoon.
After searching for nearly 16 hours, crews found Lane's body intact not far from the shore where the alligator grabbed him, the report states. A medical examiner determined he had a traumatic neck injury and drowned.
At least two people reported to Disney workers seeing an alligator in the water before the attack.
Florida Fish and Wildlife Conservation Commission officers captured, examined and killed six alligators during the search for Lane's body. Two females, both about 7 feet long, were caught near the beach, according to a commission report also released Monday.
Officials tested both for evidence of an attack but couldn't find anything conclusive, although they surmise that one was responsible, the report states. Both had empty stomachs.
Witnesses described an alligator of about that size.
"The victim could have been mistaken for some of the animal's normal prey like opossum, armadillo or raccoon," officials wrote.
Since the attack, Disney workers have been building wide boulder walls along the Seven Seas Lagoon beach in an effort to keep alligators away from guests. They also put up signs warning of alligators and snakes.
The family announced last month that it would not sue the resort.
Allen writes for the Orlando Sentinel.
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