Eighteen commuters were injured when the entire roof of a double-decker bus was torn off after it hit a tree.
Seven people were taken to hospital after police, ambulance and fire services were called to the accident on Fishponds Road, Bristol.
The accident involved the 342 First Bus service that was travelling down the busy main road when it hit the low hanging tree branch.
Those injured had been travelling on the upper level of the double decker. The ripped-off roof landed 100 yards further down the road from where the bus came to a stop.
Jonathan Pomeyie told the BBC he was at the back of his house making a cup of tea when he heard a loud bang.
"It was a very deep impact type of sound, like an explosion.
"I saw police, paramedics and firemen everywhere. It was a horrid and unbelievable sight to wake up to."
Ambulance crews, including doctors with specialist trauma training, treated seven passengers who were taken to hospitals in the area.
Although none were believed to be suffering life threatening injuries, a man in his twenties, who had been trapped in the bus, was taken to Frenchay Hospital with a suspected back injury.
Eleven people were treated at the scene, near the junction with Alcove Road, with patients suffering cuts and bruises to their heads.