Alejandro Chaskielberg named Sony world photographer
Alejandro Chaskielberg is the Sony world photographer of the year, it has been announced.
The 34-year-old won the L'Iris D'Or for his photos of a community of islanders living on the Parana River Delta in his native Argentina.
Chaskielberg lived with the residents for two years to document their lives for his series of striking pictures.
He was presented with the award plus a $25,000 (£15,100) cash prize at a London ceremony on Wednesday.
"This year's panel of judges found no great difficulty in agreeing to honour the powerful work of Alejandro Chaskielberg's series High Tide," said Francis Hodgson, chairman of the honorary judging committee.
"These carefully directed pictures tell solid truths - about toil and communality and marginal economic survival - in a splendidly allusive way."
The Open photographer of the year title was awarded to Chan Kwok Hung for his dramatic image, Buffalo Race.
The 37-year-old jewellery manufacturer from Hong Kong purchased his first SLR camera in 2006 and taught himself basic photography skills using books and the internet.
American photographer Bruce Davidson also collected the award for outstanding contribution to photography.
The 77-year-old's past work has included following a Brooklyn gang in the 1950s and chronicling the civil rights movement in the early 1960s.
Other awards presented at the ceremony included the professional category winners covering current affairs, to travel and fine art portraiture.
Over 105,000 images were entered into the 2011 competition from 162 countries.