FIREMEN have issued a warning after children were found playing with a propane gas cylinder on derelict land. Firefighters were called to Blackleach Drive, Walkden, last night after a passer-by saw around 10 children playing with the cylinder. They were unharmed and the cylinder was emptied. Leading fireman Chris Glaister said: "We cannot stress enough that cylinders are not to be played with. There is always some vapour inside which can be very dangerous."