North Korea has fired more than 200 rounds of artillery shells into the sea near a tense maritime border and towards two South Korean islands, which Seoul called “an act of provocation” as it responded with live fire drills.

The exchange on Friday led residents of Yeonpyeong and Baengnyeong – two remote South Korean islands – to evacuate to bomb shelters at the instruction of Seoul’s military before it fired live rounds towards the disputed Northern Limit Line (NLL).

Pyongyang’s fire caused no damage, said Lee Sung-joon, a spokesperson for the South Korean Joint Chiefs of Staff, adding that all the shells landed on the northern side of the sea border.

“This is an act of provocation that escalates tension and threatens peace on the Korean Peninsula,” South Korean Defence Minister Shin Won-sik said as he supervised the firing drills.

North Korea said its defensive coastal units fired 192 rounds as a “natural response” to military actions by South Korea’s “military gangsters” in recent days, the official Korean Central News Agency (KCNA) reported.

It also threatened an “unprecedented strong response” if Seoul continued to make provocative moves.

The Ministry of National Defense in Seoul said the military was closely monitoring the situation in coordination with the United States.

Marine brigades based on the two islands fired into the sea to the south of the NLL, demonstrating “overwhelming operational response”, the ministry said. Its drills involved mechanised artillery and tanks.

An official on Yeonpyeong island, which sits just south of the NLL, confirmed that residents were told to move into bomb shelters at the request of the military. Residents of Baengnyeong island, located west of Yeonpyeong and near the sea border, were also directed to evacuate, as confirmed by a village official.

North Korea said its drills had no impact on the islands, calling Seoul’s claims “an attempt to mislead public opinion”, according to KCNA.

Since the 1990s, Pyongyang has disputed the NLL – drawn up at the end of the 1950-1953 Korean War – arguing it should lie far to the south.

In 2010, North Korean artillery targeted Yeonpyeong, resulting in casualties, including civilians. Pyongyang asserted it was provoked by Seoul’s live-fire drills that dropped shells into its territorial waters.

China calls for ‘restraint’

“Under the current situation, we hope that all relevant parties maintain calm and restraint, refrain from taking actions that aggravate tensions, avoid further escalation of the situation and create conditions for the resumption of meaningful dialogue,” Chinese Ministry of Foreign Affairs spokesperson Wang Wenbin told reporters on Friday.

China is a key ally of North Korea.

“Confrontations between relevant parties have intensified recently, and the situation on the peninsula continues to be tense,” Wang said.

This week, North Korean leader Kim Jong Un ordered his military to “thoroughly annihilate” South Korea and the United States if they initiate a military confrontation in another round of bellicose rhetoric targeting Seoul and Washington.

The relationship between the two Koreas has been at its lowest point in decades of strained relations.

North Korea has recently ramped up its nuclear and military threats, successfully launching a reconnaissance satellite on its third attempt in November and in December testing the solid-fuel Hwasong-18, its most advanced intercontinental ballistic missile, for the third time in 2023.