Mexico's Amat Escalante wins Cannes best director

The 34-year-old director, who was forced onto the defensive after the violence left some members of the audience uneasy, paid tribute to this year's Cannes jury headed by Steven Spielberg.

"This earthquake, I wasn't expecting this! Thank you to this brave jury... to Mexico, I hope we never get used to suffering... " he said.

"Heli" tells the story of a family caught up in gangland battles in an unnamed desert region of contemporary Mexico and contains protracted torture scenes.

In one scene, a character sets the genitals of a suspected cocaine thief ablaze.

Escalante reacted to criticism of the film by calling it an accurate depiction of the situation in underworld crime-blighted Mexico.

And he dismissed critical questions about upsetting audiences.

"What's the point of not showing the violence just so the audience can go through the story and not suffer so much when actually that's not how violence is in real life?" he asked reporters.

"I think I'm curious about sex and death and violence, and so that's all in the film," added Escalante, whose last picture "Los Bastardos", set among the Mexican community in Los Angeles, played in Cannes' Un Certain Regard section in 2008.

"Heli" features amateur actors, telling the story of a police cadet who falls for the 12-year-old sister of a factory worker named Heli (Armando Espitia).

Film industry bible Variety called "Heli" "an accomplished but singularly unpleasant immersion" in the drug wars and noted that it was the most "explicit, realistically violent film" in the Cannes competition in several years.

However Robbie Collin, a reviewer for London's Daily Telegraph, said: "Even a bleak existence can make an uplifting story."