OTTAWA -- The Correctional Service of Canada apologized on Friday for wrongly saying it called police right away when it heard allegations that a guard at the Nova Institution for women had sexually assaulted an inmate.

In fact, the federal correction service waited three months to contact police while it conducted an internal investigation of alleged incidents at the multi-level facility in Truro, N.S.

Waiting to report allegations to police while internal probes play out is a common complaint about how institutions with authority over potentially vulnerable people, such as schools, churches and athletic organizations, respond to concerns of sexual assault.

On Wednesday, the Correctional Service insisted that it had, in fact, notified police right away.

"Please note, as soon as allegations of misconduct were brought forward we began our investigation and notified our police partners of the matter," it said in a statement.

The service changed its story on Friday, however, in response to questions from The Canadian Press.

"We have reviewed the timeline of our co-operation with the police," it said. "We apologize for communicating the timing of CSC's contact with the police in error. As the police are investigating, and this matter appears to be before the courts, we are unable to provide any further details."

The service also said it followed Treasury Board guidelines in putting the officer on administrative leave during that investigation, and contacted police with details from the review on March 29.

Truro Police Chief David MacNeil said this week that police began an investigation on March 28 after receiving a complaint.

"As this is an open and active investigation we can't comment any further at this time," he said.

The correctional service said Friday that when it contacted Truro Police, the force indicated it had "recently received a call."

"There was no indication made that an investigation was already underway," it said.

The correctional service now faces a lawsuit from three women who say they were assaulted at Nova -- one of six federal institutions for women in Canada.

In response to the launch of the lawsuit, the director of advocacy and legal issues for the Canadian Association of Elizabeth Fry Societies, Savannah Gentile, called the women "incredibly brave" for coming forward, adding the "fear of reprisal" is a common and founded fear in prison.

Halifax lawyer Mike Dull said Wednesday that two of the three women are still serving time.

On Wednesday, a spokesperson for Public Safety Minister Ralph Goodale said the federal government cannot comment on court cases but stressed the minister expects the Correctional Service of Canada to ensure all allegations of sexual assault are thoroughly investigated.