There's shock among parishioners at a Catholic Church in Ottawa Thursday after learning an elderly priest has a prior conviction of sexually abusing young girls.

Father Jack McCann spent 10 months in jail for offences he committed in B.C. in the 1970s. He now lives in Ottawa where he's presided over masses at Our Lady of Mount Carmel Church in the city's east end.

The congregation loves him. But they weren't aware of his past until just recently.

"Very, very surprised. You must have the wrong priest," parishioner Darlene Rodda told CTV Ottawa.

Even the parish priest who works with McCann wasn't aware of his past. He just learned about McCann's conviction a few days ago after CTV started making phone calls.

"I was horrified to find out that I didn't have any knowledge of that and was never told about his background at all," said Father Stephen Liang.

McCann served as a priest in New Westminster, B.C. in the late 1970s. In 1992, he pleaded guilty to sexually abusing two young girls -- and was sentenced to 10 months in jail.

CTV Ottawa tried to speak to McCann, but he didn't want to talk.

Although he's served time for his crime, sexual abuse survivors say he should not be allowed to continue work with the Church.

"He should be defrocked. If he were in a daycare setting and was convicted of sexually abusing kids, no one would consider returning him to that daycare setting," said Rob Talach, a lawyer for sexual abuse survivors.

A spokesperson for the Archdiocese of Ottawa told CTV that McCann is not in active ministry and cannot celebrate mass without the supervision of other priests or bishops. However, that's exactly what he's been doing.

"Yes, he was saying mass on his own," Liang told CTV Ottawa.

The Archdiocese says it's dealing with the issue and Liang has been told that McCann won't be allowed to say any future masses.

The Church plans to hold a special prayer session on Saturday morning to tell parishioners that McCann has withdrawn from the parish for personal reasons.

With a report from CTV Ottawa's Joanne Schnurr