The Guardian and The Washington Post shared a Pulitzer Prize for reporting on leaks from former US National Security Agency contractor Edward Snowden that revealed a global surveillance network monitoring millions of Americans and foreigners.
The British and American newspapers won the award for public service journalism given by the Pulitzer committee on Monday at Columbia University in New York, for sparking debate on secretive NSA programmes.
The shared award went to the two newspapers credited with breaking the news about NSA surveillance, without specifically citing the journalists involved.
Both newspapers relied on documents leaked by Snowden, a former NSA contractor who has been granted temporary asylum in Russia and is being sought for prosecution in the US.
The reporters who played key roles in the story included Glenn Greenwald, who has since left The Guardian, and colleague Ewen MacAskill. Barton Gellman, who already has two Pulitzers, was the writer of most of The Washington Post reports.
Laura Poitras, a documentary filmmaker who was the point of contact for Snowden, had the unusual distinction of sharing bylines in both The Guardian and the Post on the topic.
In arguably the most influential story of the decade, The Guardian and Post broke sensational ground by exposing how the US government monitors the data of millions.
Sig Gissler, administrator of the Pulitzer Prizes since 2002, said the choice was complex and that the prize was "really not focused on Mr Snowden". He said the two newspapers "helped stimulate this very important discussion about the balance between privacy and security".
Snowden, in a statement released to The Guardian, said that the Pulitzer decision "is a vindication for everyone who believes that the public has a role in government".
The Guardian said: "We're extremely proud and gratified to have been honoured by the Pulitzer board. It's been an intense, exhaustive and sometimes chilling year working on this story and we're grateful for the acknowledgment by our peers."
Post executive editor Martin Baron said the reporting exposed a national policy "with profound implications for American citizens' constitutional rights" and the rights of individuals around the world.
Republican congressman Peter King, a member of the US House Intelligence Committee, expressed his disapproval on Twitter, saying: "Awarding the Pulitzer to Snowden enablers is a disgrace."
Among the other Pulitzers, The Boston Globe staff won the breaking news award "for its exhaustive and empathetic coverage of the Boston Marathon bombings and the ensuing manhunt that enveloped the city, using photography and a range of digital tools to capture the full impact of the tragedy".
The New York Times won awards for breaking news photography as well as for feature photography.
Jason Szep and Andrew Marshall of Reuters won the international reporting award for coverage of the Rohingya, Myanmar's persecuted Muslim minority.
The editorial cartooning award went to Kevin Siers of The Charlotte Observer, who also tackled the NSA as a subject.