The small German city of Braunschweig is in the grips of a mystery.

Envelopes stuffed with 500 euro notes have been turning up at the offices of various charities around town.

It's not known who is leaving the money, so the German press are affectionately calling the anonymous donor a 'modern day Robin Hood'.

Local priest, Hans-Juergen Kopkow, found his church was 10,000 euros better off after finding the stash behind some hymn books.

SOUNDBITE: Hans-Juergen Kopkow, Priest of St. Markus church, saying (German):

"It's extraordinary that someone would actually anonymously donate such a huge sum of money, and it is a huge sum of money, and that they wouldn't want to be identified and don't expect anything in return."

So far 190,000 euros has been found.

Alfred Huge's Meals-on-Wheels charity is one of the latest organisations to benefit.

SOUNDBITE: Alfred Huge, Manager of the Braunschweig Meals on Wheels, saying (German):

"I don't know if it's a man or a woman, young or old, I just don't know. Sometimes I would like to know, I'd like this person to reveal themselves so I could just look them in the eyes and say thank you."

The mystery benefactor has become the talk of the town and there are various theories as to whom they may be.

SOUNDBITE: NO NAME GIVEN, PASSER-BY, SAYING (German):

"It's a really likable person who looks out for the weakest in society. I think it's a great idea if you're able to do it, maybe I would do it too."

SOUNDBITE: NO NAME GIVEN, PASSER-BY, SAYING (German):

"How often do you hear of something like this. I think it's great that someone would give their money for good causes."

The identity of the donor may never be known but the residents and especially the charities of Braunschweig hope this fairytale story never comes to an end.

Hayley Platt, Reuters.