The crash happened at about 4pm on Tuesday afternoon as the Centrebus school service took around 40 pupils home from the Coteland's School, Ruskington.

From the school, the bus heads across to Leasingham before following Lincoln Road into Sleaford and out on the Grantham Road. According to the bus company, as it was travelling along Moor Lane towards Leasingham, its wheels slipped off the tarmac and slid into a ditch at the side of the road, coming to rest leaning against a line of small trees.

Graham Webster, deputy headteacher at Cotelands was down at the scene 10 minutes after it happened and said they were just relieved that no-one had come out with worse than shock and bruises. Three children stayed off school the next day as a result.

He said: "There was almost a moment of hysteria when it first happened but then pupils reacted in different ways – some tearful, others almost laughing."

Staff from Cotelands, Lafford and Ruskington Winchelsea schools were passing and assisted in controlling the situation and getting everyone organised.

Mr Webster said: "Normally you would expect the bus to fall over but landing on the row of tree kept it upright. It was at an angle of 45 degrees and had it gone all the way over it would have been much more serious with broken glass and head injuries."

As the bus was leaning against the main doors, children had to get out through the emergency exit. Mr Webster said: "They had to literally kick that open because they had to climb up to it and force it with their feet due to the angle the bus was leaning."

Centrebus operations manager Alan Humphries said his driver, a man from Yaxley, went slightly onto the grass verge as an oncoming car passed and the bus slid on the soft ground.

He said: "Fortunately no-one was hurt. Our driver went through the proper procedure. He got everybody off and got another bus out there as soon as we could."

It took until the early hours of the morning for a crane to haul the bus out of the ditch and clear the lane. Mr Humphries added: "It takes a lot to put one of them over and I don't believe it would have gone over looking at the way it landed.

"I am sorry it has happened. We don't want anything like this happening with schoolchildren on board, but it is not an everyday occurrence."

* Were you on board the bus? Did you take pictures? Send in your photos to andy.hubbert@jpress.co.uk or text to 81800 – start your message with SLEANEWS followed by your message. Please include your name and address.