Bundles of cash found on the streets of a former pit village were left by two Good Samaritans, police have said.
Since 2014 there have been at least 12 instances of money being found in Blackhall Colliery, County Durham, usually amounting to £2,000 in £20 notes.
The money was always left in plain sight and often on pavements.
The benefactors told police they had received unexpected windfalls and wanted to give something back.
One of the Good Samaritans - who both wish to remain anonymous - said she felt an "emotional connection" to the former pit village after being helped by a resident and wanted to "repay the kindness she received".
Over the past six years £26,000 has been handed in by village residents.
Durham Police said all the previous bundles had been returned to the finder.
The benefactors would deliberately leave the money where it would be found by people in need, including pensioners, and they would then often wait to make sure it was picked up.
Det Con John Forster, of Durham Police, said he was "really pleased" the mystery had been solved.
He added: "I am glad we can now definitively rule out the money being linked to any crime or a vulnerable person.
"I would like to thank the Good Samaritans for getting in touch and also to the honest residents of Blackhall who have continued to hand the money in."
It is unknown whether the pair will continue to leave bundles of money but any that are found and handed in to police will continue to be returned to the finder.