A Bristol night bus has been vandalised as it travelled from Westbury-on-Trym to Henbury.
The emergency hammer was used to smash 16 windows and two seats were ripped out during the incident on 9 November.
As a result, police are escorting buses through Henbury and are carrying out covert and high visibility patrols in the Crow Lane area.
Beat manger Pc Chris Denny said: "This was a terrifying ordeal for the bus driver.
"There were about 60 passengers on board who must know or be able to identify or describe those responsible.
"We would urge them to come forward either in person at Avonmouth Police Station or anonymously though Crimestoppers."