Greece's financial crisis has made some families so desperate they are giving up the most precious thing of all - their children.

One morning a few weeks before Christmas a kindergarten teacher in Athens found a note about one of her four-year-old pupils.

"I will not be coming to pick up Anna today because I cannot afford to look after her," it read. "Please take good care of her. Sorry. Her mother."

In the last two months Father Antonios, a young Orthodox priest who runs a youth centre for the city's poor, has found four children on his doorstep - including a baby just days old.

Another charity was approached by a couple whose twin babies were in hospital being treated for malnutrition, because the mother herself was malnourished and unable to breastfeed.