RALEIGH, N.C. — Outgoing North Carolina Gov. Beverly Perdue issued pardons Monday to the Wilmington 10, a group wrongly convicted 40 years ago in a notorious Civil Rights-era prosecution that led to accusations that the state was holding political prisoners.

Perdue issued pardons of innocence Monday for the nine black men and one white woman who were given prison sentences totaling nearly 300 years for the 1971 firebombing of a Wilmington grocery store after police shot a black teenager.

The pardon means the state no longer thinks the 10 — four of whom have since died — committed a crime.

“I have decided to grant these pardons because the more facts I have learned about the Wilmington 10, the more appalled I have become about the manner in which their convictions were obtained,” Perdue said in a news release Monday.

The three key witnesses in the case later recanted their testimony. Amnesty International and other groups took up the issue, portraying the Wilmington 10 as political prisoners.

In 1978, then-Gov. Jim Hunt commuted their sentences but withheld a pardon. Two years later, the 4th U.S. Circuit Court of Appeals in Richmond, Va., threw out the convictions, saying perjury and prosecutorial misconduct were factors in the verdicts.

“We are tremendously grateful to Gov. Perdue for her courage,” said Benjamin Chavis, the former national NAACP executive director who was in jail and prison for about five years before his release. “This is a historic day for North Carolina and the United States. People should be innocent until proven guilty, not persecuted for standing up for equal rights and justice.”

In addition to Chavis, the surviving members of the Wilmington 10 are Reginald Epps, James McKoy, Wayne Moor, Marvin Patrick and Willie Earl Vereen. Those who have died are Jerry Jacobs, Ann Shepard, Connie Tindall and Joe Wright. Wright was the youngest, arrested when he was 16 years old.

The Wilmington 10 were convicted in October 1972 on charges of conspiracy to firebomb Mike’s Grocery and conspiracy to assault emergency personnel who responded to the fire in February 1971.

The trial was held in Burgaw in Pender County after a judge declared a mistrial the first time. A jury of 10 blacks and two whites had been seated in the first trial when prosecutor Jay Stroud said he was sick, and the judge declared the mistrial. At the second trial, a jury of 10 whites and two blacks was seated.