A window was smashed on a rail replacement bus in Preston after a group of youths threw stones at passing vehicles, say police.
Police received reports of the youths throwing stones on Broadgate at around 9pm on Sunday, January 28.
Officers released a photo of the smashed window and revealed that thankfully, the bus was empty at the time of the incident.
Police in Preston are now asking parents to make sure they know where their children are and what they are doing.
A police spokesman said in a post to social media: "Do you know what your kids are up to tonight?
"We have had multiple reports of kids throwing stones at passing cars and buses in Broadgate.
"This bus luckily had no passengers but the results could have been worse."
No arrests have been made.
Anyone with information can contact police on 101 quoting log reference 1451