I want the history of weapons?

Concern focuses around two reactors at the Yongbyon Nuclear Scientific Research Center, both of them small power stations using Magnox techniques. The smaller (5MWe) was completed in 1986 and has since produced possibly 8,000 spent fuel elements. Construction of the larger plant (50MWe) commenced in 1984 but in 2003 was still incomplete. This larger plant is based on the declassified blueprints of the Calder Hall power reactors used to produce plutonium for the UK nuclear weapons program. The smaller plant produces enough material to build one new bomb per year; if completed, the larger plant could produce enough for 10 each year . It has also been suggested that small amounts of plutonium could have been produced in a Russian-supplied IRT-2000 heavy-water moderated research reactor completed in 1967, but there are no recorded safeguards violations with respect to this plant.