The manager of the Hospiscare shop in Exeter was stunned to discover that the bag had been left outside the store along with other items. Inside were wads of used £20 notes.
Devon and Cornwall Police are now asking for the donor to come forward and confirm that the money was legitimately intended for the charity.
They're currently holding on to the dosh, but if no-one has got in touch in the next six weeks, it will stay with Hospiscare.
A spokesperson for the police was quoted on the BBC saying: "It was left before the shop was opened and all we are trying to do is confirm that it was the donor's wish to give the money to the charity."
Glynis Atherton, chief executive of the charity explained: "The manager was amazed and immediately contacted the police."
She added: "If it's intended for us it would be a huge boost to our work. The sum would provide almost a week of 24 hour wraparound care in our hospice."
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