Murray said the school has sought advice from the Education Authority’s Critical Incident Response Team who will be available to support pupils affected by the incident.
“I would encourage pupils, if they feel well enough, to attend school tomorrow where staff will signpost them to the support services available,” he said in his letter.
“The thoughts and prayers of the St Paul’s community are extended to everyone affected by this serious incident today.”
The Education Authority said it was providing “critical incident management support to the school”.
“Our critical incident team will be in the school tomorrow to provide emotional support for pupils as required,” a spokesperson said.
“Our thoughts go out to all of those impacted by the incident.”