How to separate image into non overlapping (MxM) image and apply DWT using blockproc ?

InImg = imresize(imread('peppers.png'),[120,120]);
figure,imshow(InImg)
% Apply DWT Process
fun = @(block_struct) dwt2(InImg,'haar');
I2 = blockproc(InImg,[8 8],fun);
figure,imshow(I2)