The Nicholsons car park is closed and has been without power without 5.55pm yesterday.
According to the Royal Borough, a power failure to the site is being ‘urgently investigated’ and the car park will not be reopened until it is restored.
It may not be reopened until later this afternoon, but a Royal Borough spokesman said: "The council has stressed to the utility companies the importance of getting this resolved as quickly as possible."
It said there has also been an issue with a 'small gas explosion' in King Street shortly after the outage.
Accessibility charity People to Places, which is based in the car park, is closed due to the loss of power.
The council said VMS signs on roads leading into the town, which indicate how many spaces car parks have free, are not working and a contractor is working on a solution.
Click here to see a list of alternative car parks in the town.
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