— A juvenile loggerhead sea turtle found along the central North Carolina coast last week was beaten to death, officials said Friday.

A National Park Service ranger found the turtle July 26 on the Portsmouth flats of North Core Banks. The animal was still alive at the time, but treatment at the North Carolina State University College of Veterinary Medicine couldn't save it, and it died three days later.

The vets that performed a necropsy on the turtle said the animal died of blunt force trauma to the brain, but they found no sign of more distributed trauma that would indicate the turtle had been hit by a boat.

"It is difficult to devise a plausible explanation for the focus, shape and severity of the fractures other than an intentional malicious blow to the head with something like a hammer to a turtle that was not free-swimming at the time," the vets wrote in their report.

The wound was one to three weeks old, and the turtle likely was restrained in the water when it was beaten and left to die, the vets said.

"If it is true that this loggerhead turtle was killed by a human hand, we want to know who,” Tim Gestwicki, executive director of the North Carolina Wildlife Federation, said in a statement.

The group, along with the Coastal Conservation Association of North Carolina and an unidentified individual have donated $7,500 as a reward for information leading to an arrest and conviction in the case.

"We are providing these resources to underscore the seriousness we place on killing any turtles. This blight on the entire state must be halted. This type of wanton waste will not be tolerated," Gestwicki said.

State and federal law enforcement agencies are investigating the turtle's death. All sea turtles are on the federal and state Endangered Species lists, and the crime is a felony punishable by a fine up to $100,000.

Anyone with information about the case is asked to call the state Wildlife Resources Commission toll-free at 800-662-7137.