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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Wales head coach Rob Howley admitted his side's performance 'simply wasn't good enough' against Scotland this afternoon.
It will be cloudy with outbreaks of rain at first, but most of the rain will clear by morning.
Despite leading at half time, Howley's men failed to score in the second half with Scotland racking up 20 points to seal the win.