'Kick-Ass 2' producer Mark Millar is ''baffled'' after Jim Carrey withdrew support of the film.

The actor - who plays Colonel Stars and Stripes in the superhero sequel - controversially claimed he couldn't support the film's release due its graphic violence following the Sandy Hook school shootings last year, however, the film's producer has hit back at Carrey suggesting that he was well aware he had signed up for a boundary-pushing movie.

Writing on his Millarworld website, he said: ''As you may know, Jim is a passionate advocate of gun-control and I respect both his politics and his opinion, but I'm baffled by this sudden announcement as nothing seen in this picture wasn't in the screenplay eighteen months ago.

''Yes, the body-count is very high, but a movie called 'Kick-Ass 2' really has to do what it says on the tin. A sequel to the picture that gave us Hit-Girl was always going to have some blood on the floor and this should have been no shock to a guy who enjoyed the first movie so much.''

The actor previously expressed his love of 2010's 'Kick-Ass', which starred Aaron Taylor-Johnson and Chloe Grace Moretz, and couldn't resist the opportunity to sign on for the sequel.

However, Carrey - who filmed his scenes for the action film last year - has now denounced the film following the shooting at Sandy Hook Elementary School in Newtown, Connecticut, last December, in which 20 children and six adults were killed.

He wrote on Twitter yesterday (23.06.13): ''I did Kickass a month b4 Sandy Hook and now in all good conscience I cannot support that level of violence.

''My apologies to others involve with the film. I am not ashamed of it but recent events have caused a change in my heart. (sic)''

'Kick-Ass 2', directed by Jeff Wadlow, is due for release in August.