(ATTN: UPDATES throughout with details; CHANGES dateline)
PUNGGYE-RI, May 24 (Joint Press Corps-Yonhap) -- North Korea destroyed its only known nuclear test site with a series of explosions over several hours on Thursday, taking an initial step toward denuclearization, according to South Korean journalists visiting the area.
The North dynamited the No.2 underground tunnel in the North Portal at Punggye-ri, a northeastern remote area, at around 11 a.m., they said in a brief pool report delivered by phone.
Two other tunnels were destroyed at 2:17 p.m., followed by the explosion of barracks, observation towers and other facilities on the ground.
The blasts ended at 4:17 p.m., the journalists said without clarifying whether the No. 1 tunnel was removed as well.
Reporters and television crews from the United States, China, Russia and Britain were also invited to witness the ceremony.
The South Korean government welcomed the move, expressing hope for further progress in efforts for a nuclear-free Korea.
"(We) expect it to serve as a chance for complete denuclearization going forward," Noh Kyu-duk, spokesman for the Ministry of Foreign Affairs, told reporters.
As the North's media remains silent about the event, it was not immediately confirmed whether the North's leader, Kim Jong-un, visited the site to observe the closure of the symbol of the communist nation's nuclear program.
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