A bus and lorry have crashed on the A120 near Colchester. A number of children and adults on the bus were injured.
The East of England Ambulance Service sent four ambulances to the scene near Great Bromley.
Essex Police said: "A bus, carrying children and adults, had been in collision with a lorry.
"Nobody is believed to have been seriously injured but a number of people are being treated by paramedics for minor injuries."
"The road is likely to be closed for some time while we investigate and the vehicles are recovered."