Thieves struck at the Old Station Buildings, home to the Platform entertainment venue, on Monday evening (November 13).
The theft became evident later on Tuesday when, as a result of heavy rain, water began to pour through the roof from where the lead flashing had been taken.
Although emergency repairs are taking place and should be completed by the weekend, Friday’s show by comedian Mark Watson has been cancelled as a precaution.
A tea dance tomorrow (Thursday) has also been cancelled. No other shows are currently affected.
Coun Darren Clifford, Cabinet member with responsibility for leisure, culture and tourism, said: “We’re in the process of making emergency repairs to ensure the Platform is back up and running as soon as possible.
“I would urge anyone who may have information on who was responsible to get in touch with the police so these thieves can be caught before they strike again.”
Anyone with information on the theft is urged to call Lancashire police on 101.
Last updated: 15 November 2017