Cars are being broken into at rate of more than one a day, according to police.
Since the beginning of November there have been 51 break-ins in the town.
One hot spot for vehicle crime is Victoria Road near the hospital.
Police have warned owners to be vigilant against thieves by locking their doors and make sure valuables such as bags, holdalls and sat navs are not on show.
Inspector Steve Griffiths promised to step up patrols in the areas commonly targeted.
He said: "The majority of the offences were committed overnight and at least 50 per cent involved secure vehicles having their windows smashed in order to gain entry.
"Along with the smash and grab method, in over 30 per cent of offences offenders have entered through insecure doors.
"These are clearly opportunists trying car door handles. If your door is locked you are less likely to become a victim of crime.
"You can also lessen your chances of being a victim by ensuring valuables aren't on show such as bags, holdalls and sat navs.
Inspector Griffiths also urged residents to report the sound of smashing glass or anything suspicious.
