Are these ATC bricks from the 1970's LEGO? I have some Lego compatible basic bricks from early 1970s or late 1960s. Bought in Finland or maybe Germany or Sweden. Can anyone tell me more about them? 

As you can see, the interlocking mechanism is different, but fits with normal Lego bricks. The colours are normal Lego white, blue, yellow, red, and black, save for one piece that is bright green. 



Here's another photo where you see the logo and interlocking mechanism nearer:
ATC is the Asahi Toy Company from Japan. Here are the pages from their 1971 catalog showing some of their construction sets: