South Korea's military fired warning shots after North Korean soldiers crossed the Military Demarcation Line near the border on Tuesday, according to the country's Joint Chiefs of Staff (JCS).
Some 20 to 30 soldiers breached the line by 20 metres (65 feet) inside the demilitarised zone on Tuesday morning and briefly moved back north after warning shots were fired by the South, according to a JCS official.
The JCS does not think the breach was intentional, the Yonhap news agency reported.
North Korean soldiers also suffered multiple casualties while working due to the explosion of landmines in the demilitarised zone, the JCS official told the press.

Xi, Putin hail ties in video call as Ukraine war nears anniversary
Israeli strikes kill 21 in Gaza, health officials say
Nestle widens infant formula recall after France lowers toxin level
UN Chief warns two-state solution slipping away amid West Bank expansion
Pakistan sends helicopters, drones to end desert standoff; 58 dead
