Kathryn Bigelow has become the first woman to win the best directing Oscar, as her Iraq war drama The Hurt Locker took six prizes including best film, BBC News reports. "It's the moment of a lifetime," said Bigelow - only the fifth woman to be nominated in Academy Awards history.

Jeff Bridges and Sandra Bullock won the top acting Oscars for their roles in Crazy Heart and The Blind Side. Bridges, playing a hard-living country singer, beat George Clooney, Morgan Freeman, Jeremy Renner and Britain's Colin Firth to win on his fifth Academy Award nomination. "Thank you mum and dad for turning me on to such a groovy profession," said a delighted Bridges, 60. "This is honouring them as much as it is me."

An emotional Bullock picked up the coveted best actress award, just a day after winning the Razzie for worst actress, for her role in All About Steve. "Did I really earn this, or did I wear you all down," she joked. The 45-year-old praised her fellow nominees - including British newcomer Carey Mulligan, Dame Helen Mirren and the multiple nominee Meryl Streep - "who inspire me and who blaze trails for us all".

Honoured for her role as real-life Southern matriarch Leigh Anne Tuohy, she dedicated the award "to the mums who take care of the babies and children no matter where they come from," before paying tearful tribute to her own mother.

Christoph Waltz and Mo'Nique were the winners of the supporting acting awards, categories they were both widely tipped to win. Waltz won for his role as a diabolical SS officer in Inglourious Basterds, while Mo'Nique triumphed for her role in Precious. Precious also picked up the best adapted screenplay award for screenwriter Geoffrey Fletcher.

Avatar and The Hurt Locker led the nominations on Sunday, with nine nominations apiece, but James Cameron's 3D sci-fi juggernaut left with just three technical awards - for art direction, cinematography and visual effects.

Speaking on the red carpet ahead of the awards, Cameron paid tribute to his best director rival Bigelow, to whom he was briefly married, and with whom he has made a number of films. "I've extolled her virtues to the world and supported her as a film-maker. I'd be tremendously proud if she won." "We feel we've already been sufficiently celebrated," he added, referring to Avatar's "tremendous box office and the nine nominations".

The Hurt Locker's screenwriter Mark Boal heralded the film's first success of the night, winning best original screenplay. Technical awards followed in film editing, sound editing and sound mixing.

Argentina's The Secret In Their Eyes pulled off a surprise win for foreign-language film over higher-profile entries that included Austrian Cannes winner The White Ribbon and France's A Prophet.

Critically acclaimed 3D film Up, also shortlisted in the best picture category, won best animated feature film. The animation also picked up the Oscar for best original score, for Michael Giacchino, who urged other would-be film-makers to "get out there and do it - it's not a waste of time".