Numbers at the end of 1948 were estimated at 60,000 regulars in addition to constabulary, railroad guards, and trainees. These troops were equipped by the Russians with captured Japanese weapons, and Russian arms were shipped into northern Korea to meet the needs of an expanding army.[18] [18] _Ibid._ It was a military force of an entirely different character that American officers organized on the other side of the 38th Parallel. The new ROK army was strictly a defensive force, trained and equipped to maintain internal security and guard the border and seacoast. Neither tanks nor military planes were provided by the Americans, who leaned backward to avoid any suspicion of creating an instrument for offensive internecine warfare. Raids by Red Korean troops across the border became a frequent occurrence throughout 1949. One of these forays, supported by artillery, was a large-scale NK thrust into the Ongjin Peninsula. Heavy fighting resulted before the invaders were driven back into their own territory. Having failed to prevent the formation of a democratic Korean government--the only government in Korea recognized by the United Nations--the Reds at Pyongyang were making every effort to wreck it. Since 80 percent of the ROK electric power originated north of the frontier, they were able to retard economic recovery by cutting off the current at intervals. There was no other unfriendly act in the Communist bagful of tricks that Pyongyang neglected to employ while its radio stations blared forth a propaganda of hatred. Early in 1950 the situation grew more tense daily as thousands of veterans returned to North Korea after serving in the Communist armies which overran China. When Radio Pyongyang began making appeals for peace that spring, it should have become obvious to practiced observers of Communist techniques that preparations were afoot for war. On 10 June 1950 the Pyongyang government announced a new plan for unification and peace after branding the top ROK officials as “traitors.” The motive behind this proposal was apparently the usual Communist attempt to divide an enemy on the eve of an aggression. For the long-planned blow fell at 0400 (Korean time) on Sunday morning, 25 June 1950. Russian-made tanks spearheaded the advance of the NK ground forces across the 38th Parallel, and Russian-made planes strafed Seoul and other strategic centers.