SEOUL, South Korea — Army engineers from North and South Korea began clearing land mines on Monday in the Demilitarized Zone between their nations as they prepared to search there for the remains of soldiers killed during the Korean War.

A similar mine-clearance operation also began in Panmunjom, a truce village in the DMZ, a buffer zone two and a half miles wide. Although Panmunjom was originally created as a neutral area, it has since been the site of armed standoff and occasional violence.

When President Moon Jae-in of South Korea and North Korea’s leader, Kim Jong-un, met last month in Pyongyang, the North’s capital, they agreed to take steps to lower tensions along the border, like the banning of military flights or drills near the frontier. The measures also included jointly searching for Korean War dead — including American and French troops — within the DMZ and disarming Panmunjom to turn it into a “peace zone” where tourists from both sides could move around freely.

When the armistice halting the 1950-53 war was signed at Panmunjom, the American-led United Nations Command agreed with Communist generals of North Korea and China to create the “demilitarized” buffer zone to keep the warring armies apart. Despite its name, the DMZ has since become the world’s most heavily fortified frontier, defended with layers of fences and numerous guard posts.