North Korea is getting ready to blow up roads that cross the heavily militarised border with South Korea, Seoul said on Monday, amid an escalating war of words after the North accused its rival of sending drones over its capital Pyongyang.

North Korea said its army units are prepared to launch strikes against South Korea if another drone carrying propaganda flyers flies into the country.

Seoul says it has detected preparations by Pyongyang to blow up its sections of inter-Korean roads. Tensions have been soaring between the two countries in recent weeks.