When breaking tnt after placing it with commands it cause it to explode, on creative and on survival. I think tha the hand react with that command as flint and steel, or fire.

Steps to Reproduce: It doen't matter if you put the others tnt IDs's (1, 2, 3...)
1. Put on the command /setblock ~ ~ ~ minecraft:tnt 1
2. Break it on crative or survival and it will explode.