A service for young adults with disabilities has been "thrown into chaos" after minibuses they use to get out and about were tampered with.
Inspector Paul Sullivan of the South East Neighbourhood Policing Team said suspects climbed over the fence to access the Kinsley Day Opportunities centre on Wakefield Road, Kinsley, and took fuel caps off two mini buses at the site.
The buses have now had to be taken off the road for safety checks, a process which could take up to two weeks.
Around 25 to 30 people who use the service have faced disruption as a result, with staff having to juggle activities and cancel arranged visit days, police said.
Many of those using the service have wheelchairs or need other adaptations and the minibuses are the only way that some can travel. They give people an opportunity to get out and about across West Yorkshire.
Insp Sullivan said: "What kind of person does this? It is really disheartening to hear that the users of this service have been put out and been disadvantaged and have had to suffer as a result.
"All their plans and activities have been thrown into chaos, for the sake of two fuel caps.
"It might not seem a lot to some people but actually it has had a significant impact on their lives."
Insp Sullivan said the incident is believed to have taken place between 5pm on Monday, November 27 and 8am on Tuesday, November 28.
Anyone with information is asked to call police on 101 or Crimestoppers anonymously on 0800 555 111.