Banbridge: Vehicle which hit bridge was prison van
A vehicle which lost its roof when it hit a low bridge in Banbridge, County Down, was a prison van.
The driver failed to notice the extent of the damage and drove on for 10 miles.
It happened as the lorry drove under a 19th Century stone bridge known as the Cut.
A spokesperson for the prison service said one of its vehicles "was involved in a road traffic incident at Banbridge on 27 November".
No other vehicle was involved and no one was injured. The incident is being investigated.
On November 28 police posted a photo of the damage, saying it was "not the smartest move".
The following day a second lorry hit the low bridge.
Officers used the image as a warning to drivers of other high-sided vehicles, advising them to know the height and dimensions of their lorries before passing under bridges.
On the PSNI's Facebook page, officers said: "This vehicle found out the clearance height of The Cut in Banbridge yesterday. It then drove on to Portadown, not realising the damage done."
Police also joked that "only the fire service are qualified to make your motor a convertible by the roadside, but you really don't want that to happen".
They reminded motorists that in the case of a collision with a railway bridge, drivers should alert Northern Ireland Railways (NIR) immediately, using the contact number advertised under the bridge.
"There's no way of telling what structural damage could be caused by a bridge strike, and those trains aren't light."
Bridge strikes have been hitting the headlines across the island of Ireland this year.
In the Republic of Ireland, Irish Rail launched a high-profile and controversial campaign warning lorry drivers to obey height restrictions.