Officer Tim Brackeen, 38, died at Carolinas Medical Center Monday morning, according to WSOC.
Investigators have identified 23-year-old Irving Lucien Fenner Jr. as the suspected gunman. He's facing first degree murder charges.
Brackeen served 12 years in the Shelby Police Department.
Governor Pat McCrory announced Monday the state is offering a reward of up to $10,000 for information leading to an arrest.
McCrory released a statement about the passing of Officer Brackeen:
"Ann and I are offering thoughts and prayers to both the Brackeen family and to the Shelby Police Department for the loss of their colleague," said Governor McCrory. "Unfortunately this is another tragic example of the dangers those in law enforcement face in the line of duty each time they put on the uniform. The state is offering any assistance possible to help bring the individual or individuals responsible for his death to justice."