PORTLAND, Maine — The leader of Maine’s Catholic church says the diocese is investigating allegations of sex abuse against a retired priest, who was tried and acquitted of sexually assaulting a teenage altar server 18 years ago.

Bishop Richard Malone said a complaint filed with the church in November alleges that the Rev. Antonin “Tony” Caron was involved in incidents from 1982 to 1986 while he was a priest at parishes in Mechanic Falls and Gray.

The 68-year-old Caron was tried in 1994 in Washington County Superior Court on charges of gross sexual assault, unlawful sexual contact, assault and sexual abuse of a minor. A jury found him not guilty after deliberating for four and a half hours following a four-day trial.

Caron was accused of sexually assaulting the then-15-year-old girl on May 9, 1992, with a pencil and his hands in the sacristy — a small, open room behind the altar — in St. James the Grater Catholic Church in Baileyville, moments before the start of a Saturday afternoon mass, according to a previously published report. His defense attorney told the jury that Caron was a homosexual and would not have assaulted a girl.

The girl told no one about the incident for a year. She confided in George Richard Nutter, a teacher at Woodland High School and her tennis coach in 1993, according to previously published reports. He was required by law to report what she had told him to law enforcement. Their investigation led to charges being filed against Caron.

His accuser was one of 10 victims of clergy abuse who met in June 2002 with now retired Bishop Joseph Gerry and other diocesan officials in what was called by the diocese a “listening session.”

Caron was placed on sabbatical when the investigation began in 1993. After the trial, he retired to Lewiston. In 2000, the church barred Caron from ministry for his involvement in a sexually explicit website, according to previously published reports.

Although the site was shut down, part of its contents were posted on the website of a conservative Catholic watchdog group. The images showed, among other things, naked men and a closeup of a man’s genitals.

The Associated Press contributed to this report.