North Korean leader Kim Jong-un has used the latest party congress as an occasion for consolidating his base for a long-term grip on power, effectively declaring the start of his own era, Seoul's unification ministry said Friday. In an assessment of North Korea's ninth party congress that concluded its seven-day run Wednesday, the ministry said in his 15th year in office, the incumbent leader declared "the Kim Jong-un era in a full sense." At the first party congress in five years, Kim was reelected as the general secretary of the ruling Workers' Party of Korea (WPK) for reinforcing the country's nuclear deterrence under his leadership. As for the grounds for such an evaluation, the ministry cited the omission of "deference" expressions toward late state founder Kim Il-sung and late former leader Kim Jong-il in Kim Jong-un's opening speech. The ministry also mentioned North Korea's touting of Kim Jong-un's achievements that the North said surpassed those of his predecessors. Meanwhile, the unification ministry said North Korea replaced about half of the party officials in the central lead