HALIFAX -- Police in Nova Scotia say they can't lay criminal charges following an investigation into long-standing allegations of physical and sexual abuse at a Halifax orphanage.

The RCMP and Halifax police issued a joint statement Thursday saying they have concluded their investigation into accusations that former residents of the Nova Scotia Home for Colored Children were abused.

"The information obtained was unable to be corroborated to meet the threshold that would formulate reasonable and probable grounds to lay criminal charges," the police said.

In March 2012, the Mounties and Halifax police began encouraging people to come forward with their allegations. Since then, investigators interviewed 40 complainants in Nova Scotia, New Brunswick, Quebec, Ontario and Alberta.

"We understand that a significant period of time has passed since these alleged instances of abuse took place and it may have been difficult for people to discuss this very challenging time in their lives," the police said.

"However, we were encouraged by the number of people that came forward to speak with police."

Former residents of the orphanage have accused some staff at the home of abusing them -- accusations that span decades. They have also called for a public inquiry but the provincial government has resisted.

Earlier this year, 63 former residents applied for a class-action lawsuit against the home and the provincial government. A certification hearing was held in October.

More than 100 people are now a part of the bid for a class-action. A court ruling is expected next June.

The majority of the claims date back decades, almost to the home's inception as an orphanage in 1921.

The home is now a short-term residential facility for children of all races.