A South Carolina parole board's decision to grant early release for a teenager who served just one year of a five-year sentence on a gun charge rattled local law enforcement because authorities said the teen was attracted to the Islamic State and plotted to kill U.S. troops in North Carolina.

The 17-year-old was not identified, but apparently benefited from the state’s lack of terrorism laws. The state could only charge him with the weapons crime and no federal charges were reportedly ever sought.

The city of York’s police chief, Andy Robinson, said terror charges could have been leveled by the federal government, but “that bureaucracy is very complicated.”

“Apparently someone in Washington decided this wasn’t worth pursuing or it wasn’t in their parameters,” he said.

Consternation over the parole board’s decision was felt widely by local law enforcement and elected officials. York County Sheriff Bruce Bryant said he was “devastated” that the teen will be released. The teen reportedly laid out plans to live in nearby Charleston with his mother and two sisters.

“This is a person who has threatened law enforcement, threatened military personnel,” he said, according to The State newspaper.

Another law enforcement official told the newspaper that he does not believe the teen’s ideals have changed and local law enforcement will request that the FBI “keep tabs on him, because we don’t have the manpower…or the capability.” The town’s mayor, Eddie Lee, echoed the concern and said he is outraged.

The teenager was identified as an American citizen whose family is from Syria.

The prosecutor charged that the boy was plotting with a Muslim militant from North Carolina to rob a gun store near Raleigh, N.C., with plans of killing soldiers as revenge for U.S. military action in the Middle East.

The teen was “wholeheartedly sincere in his beliefs, and we are very concerned for the safety of the community and the country,” Solicitor Kevin Brackett said at sentencing. “He had a plan to randomly shoot American soldiers.”

Defense lawyer B.J. Barrowclough said the parole board made the right decision. Traumatic life experiences like the death of his father and the mistreatment by a family member contributed to him being led down the wrong path, he reportedly said.

Barrowclough previously said his client didn’t want to hurt anyone in the U.S. Instead, he wanted to fight the regime in Syria that had hurt and killed members of his own family, he said. One of the teen’s lawyers said his client had an exemplary disciplinary record and did all that was asked of him in custody.

Barrowclough asked the judge for probation, saying the teen had no criminal record and was in school and working to care for his mother.

The teen’s mother and uncle also spoke to the court, saying the boy was a good youngster who believed in the laws of the U.S. and didn’t mean any harm.

FoxNews.com's Edmund DeMarche and The Associated Press contributed to this report.