Chicago priest Rev. Michael Pfleger -- a prominent religious leader popular for his activism -- has stepped aside from his archdiocese on South Side because of claims of sexual abuse that took place decades ago, The Grio reported Saturday, citing the Archdiocese of Chicago.

The parish said its Office for Child Abuse Investigations and Review received an accusation that Pfleger, senior pastor of St. Sabina Parish in Chicago, sexually molested a minor more than 40 years ago.

The 71-year old church leader said the diocese asked him "not to speak out at this time," but the priest took to social media to make public the short statement on Wednesday.

Cardinal Blase Cupich, the Archbishop of Chicago, shared the news with members of the church. He published a letter Tuesday to confirm the OCAIR was notified the day before.

The diocese, the bishop said, reported it to the Illinois Department of Children and Family Services and the Attorney's Office of Cook County State.

However, Cupich noted that the accusation had not been proven true or not, and guilt or innocence should not be assumed.

"Father Pfleger has agreed to cooperate fully with my request and will live away from the diocese while this matter is being investigated," Cupich said in the letter quoted in part by multiple reports.

In his Facebook post, the priest said his life is "more than a 40-year-old accusation" and asked his supporters to pray for him and "for the person," seemingly referring to his accuser.

The church did not reveal details of the claims against Pfleger, nor did the attorney's office of Cook County, which said it had referred the matter to the Chicago Police Department.

Telephone calls to the diocese for comment were not answered. Leaders of St. Sabina issued a statement that said they believe the allegations are without any basis and stand behind the integrity of the activist priest.

"I'm devastated, hurt, and yes, angry, but I'm first, a person of Faith, and I trust God," Pfleger said in remarks quoted by CNN. "Please keep me in prayer and the Faith Community of St. Sabina," he said.

Larry Antonsen, a leader of Survivors Network of Those Abused by Priests, shared with The New York Times that he's proud of anyone who comes forward about abuse -- even if decades later.

Authorities said they had launched an investigation but did not provide additional details.