Three blocks, called AAA, BBB and CCC exist in the image. Block AAA contains a medium black square. Another medium black square and another medium black square are inside this block. Medium black square number two is to the south of and medium black square number three is to the north of medium black square number one. Another medium black square is covered by block AAA. Medium black square number one touches medium black square number three. Within block BBB is block AAA. Block CCC covers a blue square.
Where is medium black square number one relative to BBB?