UK graffiti artist Banksy's documentary Exit Through The Gift Shop has landed a top prize at the annual Grierson Trust awards in London.
In a taped speech, he accepted the most entertaining documentary trophy, which he had spray-painted himself.
Banksy, who hides his identity, dedicated the award to graffiti artists who risk "life and limb every night".
The jury panel said the film was "original and insightful".
The awards, which took place on Tuesday night at the BFI Southbank, commemorates the pioneering Scottish documentary maker John Grierson.
Banksy joked: "This is a very proud moment for me. I've always dreamt of winning a Grierson Award ever since I first heard about them two weeks ago."
The film was screened out of competition at the Berlin Film Festival in February.
It chronicles Banksy's friendship with French videographer Thierry Guetta.
Although the artist features in the video, he appears only in shadow and he speaks through a voice modifier.
"I do like to think that in this world of graffiti art - which is essentially mindless, messy and stupid - we finally gave it the kind of documentary it deserves," he said.
Filmmaker Julien Temple was recognised for Requiem for Detroit in the best historical documentary category at the ceremony, hosted by broadcaster Sandi Toksvig
Mat Whitecross - who made his name directing Coldplay videos before making the Ian Dury Biopic Sex & Drugs & Rock & Roll - took the title for the best film about a contemporary issue for Moving To Mars - about refugees living in the UK.