Bird identification

Hi,

i live on the east coast in Essex and have just seen 2 birds hoping around the garden.

They had brown bodies and a black, white and green/blue tail feathers. Their heads were also black and white. They were quite large, the size of a crow and hopped around with as much confidence as crows and magpies do. At first the one further back I thought it was a small hawk of some description but when they got closer it was most definitely a bird, I just have no idea what? 

Any ideas? 

Unfortunately I wasn’t quick enough to get a picture.