By Helen Bushby BBC News Online, Cannes

Filmmaker and satirist Michael Moore has said he was "blown away" when his documentary on US gun culture, Bowling for Columbine, was selected for competition at the Cannes film festival.

It is the first time in 46 years that a documentary has been chosen as part of the 22 films competing at the festival, which is famed for honouring art-house movies and auteurs.

People do not go to movies to be beaten up or lectured

Michael Moore

Moore's film explores why the US has more than 11,000 gun-related deaths per year, and compares it with Canada and Europe, where he said numbers are often less than 100 per country.

It also includes an interview with actor and president of the US National Rifle Association (NRA) Charlton Heston, who staunchly defends the "right to bear arms" as cited in the Second Amendment of the US constitution.

Moore said he was stunned at getting an interview with Heston after simply turning up at his house and pressing the doorbell.

Walked out

"I rang the buzzer and out of the box came the voice of Moses," he said at Cannes.

Moore examines gun culture

But Heston walked out of the interview when Moore probed him over whether it was insensitive to hold two NRA rallies in two US towns, where pupils had killed people at their schools with shotguns.

Moore was referring to the shootings at Columbine High School, Colorado in 1999, when two teenagers killed 12 students and a teacher before shooting themselves, and also at a school in Flint, Michigan in 2000 where a boy shot his six-year-old classmate dead.

The film also includes taped footage from the security cameras in the cafeteria on the morning of the Columbine massacre.

Moore said he had a particular interest in making the film because he is from Michigan, and was "deeply affected" by the shooting in his hometown of Flint.

'Good movies'

Bowling for Columbine's serious subject matter does not stop Moore from injecting it with his trademark humour, however.

"People do not go to movies to be beaten up or lectured," he said. "People go to good movies because they like to be challenged and they definitely want to be entertained."

The shootings at Columbine shocked America

One scene sees Moore open up an account at a US bank that offers a free gun to its new customers.

Moore was incredulous when he simply had to answer a list of questions, including whether he was "mentally unstable" or not, before being handed the shotgun.

The bank teller then informed him that there were several hundred more guns in the bank's safe.

Underdogs

But Moore concluded in the film that it is not just the availability of guns in the US which contribute to its high death rate from firearms.

He also blamed the "lack of state support" in the US, which meant the poor and needy "are not taken care of", creating a society that was wary of its underdogs rather than caring for them.

Local news media also came in for criticism, and Moore said it was sensationalist, following the "if it bleeds it leads" school of journalism, making people fearful and encouraging them to buy guns to protect themselves.

The film also includes interviews with two boys who were shot at Columbine and still have bullets embedded in their bodies, but with Moore's help they managed to persuade US supermarket chain KMart to stop selling bullets.

Moore is the author of Stupid White Men which criticises US President George Bush and has topped best-seller lists in the US, the UK and Canada.

His 1989 documentary Roger & Me, about General Motors' downsizing in the US, is the highest-grossing narrative documentary ever made.

He has also directed music videos for REM and Rage Against the Machine.