The police helicopter was called out last night as two cars were broken into in Elland.
Police officers on the ground were called at 9.35pm to reports of the vehicle break-ins at the Spire Hospital in Elland Lane.
Two suspects, one described as wearing a navy hoodie and the other a black hoodie, were seen climbing over the fence and making their way towards Elland town centre.
The police helicopter was called to assist in the search at 10.05pm but the suspects were not found.
Anyone with information should call 101.