North Korea has accused US and South Korean authorities of fabricating the results of a probe that concluded Pyongyang sent small surveillance drones, or unmanned aircraft, to spy on key South Korean installations in March.

The United States and South Korea are holding massive live-fire military drills meant as a warning against North Korean aggression.

NORTH KOREA fired two shots toward South Korea at their tense border yesterday and opposing troops immediately fired back.

The South Korean military today said three apparent explosions were heard just north of the Korean border, where North Korean troops are stationed.

Soldiers of North and South Korea have exchanged fire across the border but there were no reports of injuries, South Korean military officials said.