Firefighters have expressed concern after a number of cylinders filled with toxic gases which had been in a fire vanished.
Emergency services spent several hours fighting a dangerous blaze which had metal containers full of acetylene and other gases and sheets of asbestos in it on a remote track at the end of Maple Avenue in Hindley on Sunday evening.
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However, when watch manager Mark Anderson returned on Monday to make sure the site was still safe and take photographs for evidence the cylinders had gone.
He is concerned that the circumstances of the blaze were suspicious as there was also a quantity of metal, including copper, at the secluded location.
He said: "I went there with an officer from BOC and the cylinders had gone.
"They are not safe at all. It's concerning for us. We had made the scene safe when we tackled the blaze but someone has gone back to an acetylene cylinder that has been heated by fire. It's quite troubling.
"We don't want anybody carrying an acetylene cylinder around, it shows a disregard for safety."
The matter will be reported to the police.