Ten people were injured and £35,000 worth of damage caused to a bus when it hit a vandalised road hump.
The passengers suffered cuts and bruises after the Reading Buses vehicle hit the hump in Calcot, Berkshire, on Thursday morning.
It is believed vandals had tried to move the "sump-breaker", designed to allow access for buses while stopping other vehicles from entering the road.
An inquiry has been launched and the hump has been removed temporarily.
Colin Thompson, managing director of Reading Buses, said the damage to the bus was "substantial".
He said the hump had suffered minor damage earlier in the week.
It is thought that the vandals were trying to remove it to allow other vehicles access through the road.
"People should not be silly with roads - they are not playthings," said Mr Thompson.
"Such silliness can lead to injuries."
About 20 people were on-board the bus at the time of the accident, at the point where Pollards Way turns into The Chase.