MONCTON, N.B. -- Operators of a Moncton charity with learning programs for children, where four staff members were fired last week, say they are investigating a classroom incident, but say they can't release the details of what happened.

Mary O'Donnell, executive director at Moncton Headstart, said she became aware of an incident in one of their classrooms on May 22 and details were confirmed by the next evening.

"While we are still not in a position to share any specific details, we do want to reassure you that we have taken strong steps to avoid such an incident from happening again," she wrote in a letter to parents Monday.

She said the incident was reported to New Brunswick's Department of Education and Early Childhood Development and two staff were suspended with pay.

Those two staff and two others have since been fired and the Department of Social Development has begun its own investigation.

"The Department of Social Development takes all concerns related to children very seriously and investigates any and all requests related to the safety and well-being of children," the department said in a short statement Monday afternoon

"We are unable to comment on specific cases or any cases that may be under investigation."

O'Donnell said the impacted parents were contacted by Moncton Headstart or the government.

"We would like to state that Moncton Headstart takes the safety of children in our care very seriously, and that once we were made aware of what took place, we took immediate action to avoid this happening again," she wrote.

She said staff members received refresher training on child guidance last week.

O'Donnell said she knows parents and others want to know exactly what happened, but sharing that information could compromise the investigations.

The RCMP says it has not received any complaint.

-- By Kevin Bissett in Fredericton