[stuart45]

Never seen those, although there is something similar called Intelligent Brickwork from Ibstock, for decorative details.
http://www.ibstock.com/pdfs/new-ideas/intelligent-brickwork1.pdf

 

[stuart45]

These look a bit like them as well.
http://brickblockinc.com/

 

[stuart45]

Looking at them more closely they could be concrete bricks with a deep frog, laid frog down.
It looks like the beds joints go through each course, which they wouldn't on blockwork.