A DOUBLE-DECKER school bus carrying up to 70 people has crashed in Northern Ireland. 

The Northern Ireland Ambulance Service has declared a major incident following the crash in County Down. 

BBC News NI has reported that the majority of those onboard are pupils from Strangford College.

Police and ambulance services attended the scene on the Ballyblack Road East near Carrowdore. The PSNI described the incident as a “serious road traffic collision”.

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More than 50 of those onboard have minor injuries and eight are being treated for more significant injuries at the scene.

The NIAS has warned people to only call 999 in a life-threatening situation following the incident.

In a statement on social media, NIAS said: "NIAS is currently dealing with a major incident at Carrowdore involving a bus with up to 70 passengers.

"NIAS has despatched multiple resources to the scene. Please only call 999 if your situation is life-threatening while we deal with this incident. More details to follow."

The service added: “A bus carrying more than 60 passengers has overturned. 

“NIAS has despatched multiple resources to the scene including doctors, emergency crews, advanced paramedics, rapid response paramedics, ambulance officers and the Air Ambulance with HEMS crew on board.

“Over 50 of the passengers have minor injuries, if any, with eight patients being treated for more significant injuries at the scene.

“The situation is ongoing and NIAS will release more information as it becomes available.”

Pictures on social media show the vehicle on its side in a field having left the road. Drivers are being asked to avoid the area.

The Northern Ireland Fire and Rescue Service has tweeted five applicances are at the scene of the crash.

SDLP MLA Colin McGrath posted on social media: "I hope that everyone is ok at this incident. Large numbers involved and NIAS will be stretched - plz heed their advice and also avoid the area. Thinking of all involved."