South Korea's unification minister said Tuesday that North Korea's detonation of the inter-Korean liaison office in Kaesong was already preannounced by the North and Seoul would need more details to assess the situation.

Appearing in a session of the parliamentary standing committee on foreign affairs and unification, Minister Kim Yeon-chul said, "It is something partly preannounced (by North Korea)."

"(The country) needs to study more details of the situation," Kim said as the news of the explosion broke out while the committee was in session.   

According to the defense and unification ministries, North Korea blew up the inter-Korean liaison office in its border town of Kaesong at 2:49 p.m.

It took place three days after Kim Yo-jong, the powerful sister of North Korean leader Kim Jong-un, warned that the North will demolish the "useless" communication office. (Yonhap)