A pair of death row prisoners could end up owing their lives to Black Sabbath guitarist Tony Iommi.

The Sydney Morning Herald reports that Iommi has joined the growing effort to convince Indonesian President Joko Widodo to cancel the planned executions of Andrew Chan and Myuran Sukumaran, prisoners whose death sentences for drug-related charges are expected to be carried out by firing squad.

Iommi has written a publicly posted letter to Widodo, who's a well-known heavy metal fan and has already received a separate plea from members of Napalm Death. Saying he has "seen first hand the negative impacts that drugs can have on people and their families," Iommi lauds the "great success" the Indonesian prison system has had rehabilitating Chan and Sukumaran and refers to them as "reformed men who are making a positive difference to the lives of their fellow prisoners."

"That they have been transformed so much is a real credit to the lndonesian authorities," continues Iommi. "For this reason, I would ask that you stop the execution of Andrew and Myuran. Please allow them to serve out life sentences where they contribute to the wellbeing of lndonesia and make good for the error of their previous ways. I do hope you will consider this personal appeal."

Iommi's involvement in the campaign comes through his long association with the Australian charity DoSomething, for whom he's previously worked on behalf of Rock Aid Armenia, a project whose efforts include a music school in an Armenian earthquake zone for 200 children.

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