About 40 years ago, the statement said, Collins was working at Roman Catholic High School for Boys.
"While on administrative leave, he is not permitted to exercise his public ministry pending the outcome of the investigation," the statement said. "His leave is not connected to the cases of priests placed on administrative leave following the February 2011 grand jury report."
Collins could not be reached for comment Sunday.
The archdiocese said, "No other allegation of this nature has been received against him."
An archdiocesan spokesman said Sunday the church would refrain for now from any further internal investigation.
"We wait until law enforcement takes its course before doing anything else," spokesman Kenneth A. Gavin said.
"I'm glad the archdiocese is taking action by placing him on leave," said Karen Polesir of the Philadelphia-area chapter of the national nonprofit group Survivors Network of those Abused by Priests. "Past stories and allegations have shown they never abuse just once, so it's good to get him out of ministry."
She also said she hoped authorities would urge anyone with information about possible suspicious or inappropriate conduct by Collins to contact police.
The Rev. John Flanagan, president and rector at Roman Catholic High School, said comments about Collins had to come from the archdiocesan communications office.
The archdiocese said that when the allegation was received, it immediately was passed on to law enforcement. The church statement gave no details of the accusation.
The archdiocesan Office of Investigations, Office for Child and Youth Protection, and Office of the Vicar for Clergy reviewed the information, then made a joint recommendation to Chaput, who placed Collins on leave "pending any possible action by law enforcement and a full internal investigation."
Collins has been living at St. Martha parish in Philadelphia. An announcement about his removal was made this weekend at the parish.
"Although he was in residence there, he had no formal duties at the parish, did not assist at Masses, or make visits to the school," according to the archdiocese. "The archdiocese also communicated information about this allegation to Holy Family University."
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