The church review of whether Roman Catholic bishops are doing enough to prevent sex abuse showed that at least 150 credibly accused priests had moved out of their dioceses, raising worries that offenders are living unsupervised in places where most people know nothing about them.

Among those 150 priests, auditors learned that 10 clergymen had left the country, some returning to home dioceses overseas, and at least four could not be found.

The whereabouts of the rest of the group are known to church leaders, and the report said that, where possible, bishops had complied with their new policy and sent confidential notices to the priests’ new dioceses.

But victim advocates say that sending a private letter is not enough. The church is leaving potentially dangerous offenders roaming around unsuspecting communities, they say.

Church leaders acknowledge they are still struggling with properly tracking and supervising those men.

“That’s a very complex issue,” said Kathleen McChesney, director of the bishops’ new watchdog Office of Child and Youth Protection, which oversaw the audit.

According to the review, most of the priests who moved did so after June 2002, when bishops adopted their new plan to discipline abusers and enact safeguards for children.

The policy bars priests found guilty by Catholic officials from all church work, but says little about what should be done with them afterward.

McChesney, a former FBI agent, said most of the accused clergy who moved away were in their 60s, 70s and 80s, and left their dioceses because they retired.

Since most had never been criminally charged, law enforcement officials could not investigate their whereabouts, she said.