Another way, which I just did, is to simply use a masonary bit and drill a series of holes into the mortar surrounding a single brick, you can start in the middle. Then use a brick chisel and a 4 lb mini sledge hammer (has a short handle) and break the mortar up. Then simply hit the brick with the sledge and it will easily break. Then remove the pieces. Once you have one out, the others will break easy with the hammer. The bricks are brittle so wear goggles!
Reed