Blue Valentine director Derek Cianfrance has branded other moviemakers "irresponsible" for portraying onscreen gun violence as "cool".

A debate over the way weapons are shown on film has gathered pace since a horrific school shooting in Connecticut in December (12), and Cianfrance admits he is concerned by how violence on Tv and on the big screen will affect youngsters.

He tells British newspaper The Independent, "I have kids. I can't hardly watch an afternoon football game with them without having to turn off the Tv during the commercials. It's too much. I don't know when violence was deemed such a cinematic thing."

Cianfrance is convinced Straw Dogs director Sam Peckinpah started a trend for movie violence, but he fears modern directors have taken it too far.

He adds, "I think it must have been Sam Peckinpah who started it. But Peckinpah's violence was always writhing in the flames of his characters. I felt like there was a true human suffering in his violence. Nowadays, I'm seeing violence that's so fetishised and so cool, and I can't stand it. I can't stand the irresponsibility of guns, and gun violence in movies."

The filmmaker admits he was even reluctant to feature guns in his latest collaboration with Ryan Gosling, The Place Beyond the Pines, but had to concede as weapons were a necessary part of the story: "I didn't even want to have a gun in this movie, but it's a cop and robber story - there had to be guns. I wasn't interested in how realistic I could make the brains or the blood, I was interested in the events and the adrenaline and choices that led up to this one violent moment."

Twenty young children and six adults died after they were gunned down at the Sandy Hook elementary school in Newtown, Connecticut in December (12). The incident prompted a raging debate on gun violence and whether laws in America need to be tightened to prevent another atrocity.