South Korea demands apology from Pyongyang for landmine blasts that injured three

South Korea's military has demanded an apology from North Korea for landmine blasts along their shared border that wounded South Korean soldiers earlier this month.

Three South Korean personnel were injured by explosions in the Demilitarised Zone (DMZ) - a buffer zone separating the two Koreas, on 21 September.

South Korea said on Tuesday that the blasts, which happened on South Korea's side of the DMZ, were "highly likely" from North Korean mines. It vowed to take "corresponding measures" for what it said was a violation of a decades-old armistice.

North Korea has denied responsibility for the blasts, calling Seoul's claims "groundless" and a "farce" to escalate tensions on the peninsula.

Kim Yo Jong, the powerful sister of North Korean leader Kim Jong Un, accused South Korea of "cooking up" the claims for "political and military provocation".

Kim denied suggestions that North Korean had crossed the border to plant the mines, calling it "a deliberate and planned strained assertion to shift the responsibility for escalating tension" to North Korea.

Her statement, published in state media on Wednesday, also warned the South to be "prepared for paying price for the farce of their own making."

South Korea says the mines are believed to have been laid by Pyongyang to fortify its border. In a statement on Wednesday, it called for North Korea to apologise for the blast and put an immediate stop to such fortification activities along the border.