The widespread use of expired gas cylinders in vehicles ignoring official directives is leading to a high number of accidents across the district but the administration is doing little to address the problem, locals alleged.   There were 15 gas cylinder-related accidents in the district last year.   Local sources said gas cylinders are being used in around 15,000 vehicles in the district and most them are well beyond their expiry dates. Gas cylinders are supposed to be examined after five years but owners and drivers of the vehicle are not following the rules.   Most of the drivers are unaware about the rules and lifespan of cylinders. They accused the Bangladesh Road Transport Authority (BRTA) of handing out fitness certificates in exchange for money instead of checking the vehicles. But BRTA officials rejected the allegation.