While building up their infantry strength in the DMZ sector, the North Vietnamese maintained a credible artillery threat to the allied forces in the north. With some 100 artillery pieces, rockets, and mortars ranging from 60mm mortars to 152mm field guns, the North Vietnamese had all of the major Marine bases in the central and eastern DMZ well within their artillery fan. Their Soviet-built 130mm field guns with a range of over 27,000 meters easily reached Dong Ha, about 15 kilometers south of the Ben Hai.''

1968: The Definitive Year
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