I came across Imperial Defense, a British company, who manufacturer M16 and M4 clones.

Imperial Defense MG4A5 (M4 Carbine clone)

Imperial Defense MG4A6 (M4 Commando clone)

According to this post at the MP.net forum, the guns are manufactured in Vietnam! This makes Vietnam the second communist country to manufacture M16s.

I would guess that the guns are copied off China’s Norinco CQ 5.56 (M4A1 clone).

This is not the first time a Vietnam company has manufactured clones of Western weaponry. They notably manufacture a Lee Enfield clone, the AIA M-10, much to the frustration of American Lee Enfield enthusiats who cannot import the rifle due to BATFE rules which ban firearm imports from Vietnam.