Image copyright Getty Images Image caption President Trump's assertions of generosity were probed by the Washington Post

An investigation into Donald Trump's pledges to charitable causes during the US presidential election campaign has won a Pulitzer prize.

Washington Post reporter David Fahrenthold's articles "created a model for transparent journalism" and cast doubt on Mr Trump's assertions of generosity, the Pulitzer board said.

He also revealed Mr Trump's obscene comments about women on a 2005 tape.

The Pulitzers are the most prestigious prizes in US journalism.

Mr Fahrenthold began asking questions after Mr Trump promised to donate $6m (£4.8m) to military veterans' organisations and found that, while that pledge did get fulfilled, many previous claims of philanthropic activities had been exaggerated, the Washington Post newspaper said.

Other Pulitzer winners included The New York Daily News and ProPublica, an online platform specialising in investigative journalism, for uncovering police abuse of eviction rules that saw hundreds of people, mostly poor and from ethnic minority backgrounds, forced out of their homes.

Image copyright EPA Image caption Daniel Berehulak won a Pulitzer for his images of the Philippines war on drugs

The New York Times staff won the international reporting prize for articles on Russian President Vladimir Putin's efforts to project Russia's power abroad.

The same newspaper's C J Chivers won the feature writing award for his piece detailing a US marine's post-war descent into violence.

Freelance photographer Daniel Berehulak won the Pulitzer for breaking news photography for images published in the New York Times showing the results of Philippines President Rodrigo Duterte's war on drugs.

The Pulitzers have been awarded since 1917. More than 2,500 entries were submitted for prizes in categories ranging from public service and breaking news to commentary, cartooning and photography.