A Catholic priest convicted of sexually abusing a 10-year-old boy at a Northeast Philadelphia parish from 1998 to 1999 died Sunday, just weeks after an appeal of his conviction was heard before the state Supreme Court.

The Rev. Charles Engelhardt, 67, of Wynnewood, was in the second year of a six- to 12-year sentence at the Coal Township Prison in Northumberland County, stemming from his 2013 conviction.

Engelhardt died at Geisinger Medical Center in Danville, the Associated Press reported. He had been battling heart problems and had lost 50 pounds since accusations that he molested an altar boy at St. Jerome Catholic Church first surfaced in 2009.

Engelhardt denied the charges, saying he did not remember the victim, a fifth grader.

"I've accepted this injustice, and I will continue to do so until it is righted," Engelhardt said at his sentencing in June 2013.

In July, his lawyer, Michael McGovern, filed an appeal, alleging prosecutorial misconduct.

Engelhardt, an Oblate of St. Francis de Sales, came to Philadelphia in 1983, when he joined the faculty at Northeast Catholic High School. In 1992, he joined Father Judge High, and he was there until 2000. He joined St. Jerome, where the crimes happened, in 1998.

The attacks started shortly after Engelhardt caught the boy drinking sacramental wine following a Mass.

According to the 2011 grand jury report, Engelhardt then offered him more, and asked him whether he had a girlfriend. The priest then showed him pornography featuring men and women, and asked him which he preferred. He went on to tell the victim that "sessions" with him would soon begin.

In the sacristy after a Mass the following week, Engelhardt told the victim it was time for him "to become a man," and performed oral sex on him.

Calls to the Archdiocese of Philadelphia, the Oblates of St. Francis de Sales in Wilmington, and Engelhardt's lawyer were not returned.

Editor's Note: This story was corrected to reflect that Rev. Englehardt was still a priest and had not been defrocked.