Gwent Police say they are working to establish what happened after a schoolbus left the road in the village of Llanfach this morning.
The schoolbus was carrying 20 children between 8 and 12 years old and three adults.
No injuries are reported. There have been no arrests and enquiries are ongoing. The road was closed while the bus was recovered.
Bus company Stagecoach says it will do all it can to assist police in their investigation.
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A fine and bright start to the week, with any lingering rain clearing away as we move throughout the afternoon.
A wet and windy night to come, with rain turning heavier overnight. Feeling particularly blustery in coastal areas.