The state-run Institute for National Security Strategy issued a report Sunday predicting an increase in the North's hostility as Kim Jong-un and his supporters in the military consolidate their position.
Kim Jong-un is the 20-something heir apparent to North Korean dictator Kim Jong-il and recently was named head of the powerful National Defense Commission.
South Korea's Yonhap news agency said the report warned of potential attacks on border outposts, shipping and on North Korean defectors living in the South.
"The chances of unexpected moves will increase as the North Korean military scrambles to display its loyalty" to Kim Jong-un, the report stated.
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