Vandals bricking and egging buses in Halifax and Calderdale are putting lives at risk.
One of the companies running services in the area has appealed for any witnesses to incidents such as these to contact the police.
There has also been a spate of vandalism of bus shelters in some areas.
Passengers have posted images on social media of smashed bus window glass in incidents on routes including those at Claremount Road, Boothtown, on October 30, and Illingworth Road, Halifax, on October 31.
Services operated by more than one company have been affected.
A Sowerby Bridge service saw vandals throwing eggs at the bus’s front window. and bus shelters in the town have also been subject to vandalism.
First West Yorkshire have confirmed they have had vehicles damaged by the vandalism, and it is believed Yorkshire Tiger services have also been attacked including at Rye Lane, Pellon, Halifax,
A First West Yorkshire spokesperson said today: “We can confirm that yesterday evening we had isolated acts of vandalism that resulted in damage to some of our vehicles.
“Thankfully nobody was hurt and we are now working with the Police to review the on board CCTV footage to help identify the individuals involved as these acts could have led to a serious incident.
“We would like to reassure customers that these were isolated incidents and any person with information should contact the police immediately.”