Because of the heavy concentration of industries in the area, Chongjin is also the DPRK's air pollution black spot. With the collapse of the Soviet Union and the subsequent shortage of oil to generate electricity, many factories have been shuttered. One of the first senior U.N. officials permitted to visit the area, Tun Myat, observed in 1997 when the North Korea economic crisis reached its peak, "Chongjin was like a forest of scrap metal, with huge plants that seem to go on for miles and miles that have been turned into rust buckets. I've been all over the world, and I've never seen anything quite like this."