The collapse of a disused Gypsum mine in the region has been cited as the cause of the subsidence.
While the school was closed immediately, and an appeal was made for parents to collect their children, there were no injuries.
The Health and Safety Authority said they will follow up on the incident with the owner of the mine: "We are aware that an old section of the Gypsum mine in the area (no longer in use) has collapsed. We are not aware of injuries as a result and we will follow up with the company as appropriate," the HSA said.
Here some more pictures of the ground collapse:
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That was a close shot! These children have been really lucky!
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Sources:
Irish Examiner - School in Monaghan evacuated after sinkhole appears on GAA pitch
Facebook - Gyproc statement
Comment: Why is it that all of a sudden, all over the world, the ground has become so unstable? Those mines have been there for decades, if not centuries, so what has changed? And it's also important to note, that for many of these incidents, there are no mines in the vicinity.