Xcode allocation problems with UIImagaView keep growing - objective-c

Question

I load alot of images in my image gallery and in my thumbnail gallery, every time i press a button (section) i replace the images with the right seciont's images, all ok since the 6th-7th time i do this my app crash.
So i tried build with allocation tool and i see allocation memory growing up every time i press the button! i've been aspected to see a stack memory allocation not a growing one with
initWithContentOfFile.
What am i doing wrong?
for (UIView *view in [scroller subviews]) {
[view removeFromSuperview];
}
for (UIView *view in [thumbnail subviews]) {
[view removeFromSuperview];
}
for (int i=1; i<numeroimg+1; i++) {
UIImageView *imagen = [[[UIImageView alloc] initWithImage:[[UIImage alloc] initWithContentsOfFile:
[[NSBundle mainBundle]
pathForResource:[NSString stringWithFormat:#"%#%d",sezione,i]
ofType:#"jpg"]]]autorelease];
imagen.frame = CGRectMake((i-1)*1024, 0, 1024, 704);
[scroller addSubview:imagen];
UIButton *button = [[[UIButton alloc] initWithFrame:CGRectMake((i-1)*210, 30, 200, 150)]autorelease];
[button setImage:[[UIImage alloc] initWithContentsOfFile:
[[NSBundle mainBundle]
pathForResource:[NSString stringWithFormat:#"%#%d",sezione,i]
ofType:#"jpg"]] forState:UIControlStateNormal];
[button addTarget:self action:#selector(pagina:) forControlEvents:UIControlEventTouchUpInside];
button.tag = i;
[thumbnail addSubview:button];
}

Answer 1

What am i doing wrong?
You're using +alloc to create an image:
UIImageView *imagen = [[[UIImageView alloc] initWithImage:...
but you never release imagen.

Answer 2

Try to manually drain the autorelease pool
#autoreleasepool{
UIImageView *imagen = [[[UIImageView alloc] initWithImage:[[UIImage alloc] initWithContentsOfFile:
[[NSBundle mainBundle]
pathForResource:[NSString stringWithFormat:#"%#%d",sezione,i]
ofType:#"jpg"]]]autorelease];
imagen.frame = CGRectMake((i-1)*1024, 0, 1024, 704);
[scroller addSubview:imagen];
UIButton *button = [[[UIButton alloc] initWithFrame:CGRectMake((i-1)*210, 30, 200, 150)]autorelease];
[button setImage:[[UIImage alloc] initWithContentsOfFile:
[[NSBundle mainBundle]
pathForResource:[NSString stringWithFormat:#"%#%d",sezione,i]
ofType:#"jpg"]] forState:UIControlStateNormal];
[button addTarget:self action:#selector(pagina:) forControlEvents:UIControlEventTouchUpInside];
button.tag = i;
[thumbnail addSubview:button];
}