South Korean military patrol found holes in the two-layer wire fence, which forms the South Korea's boundary of the 4-kilometer-wide Demilitarized Zone bisecting South Korea and Democratic People's Republic of Korea on early Tuesday, said South Korean Defense Ministry.

The 40-centimeter by 30-centimeter holes on either side of the fence was found around 1:46 a.m. Tuesday (1646 GMT Monday) near Cheolwon county, a town on the central portion of the 248 kilometer-long inter-Korean border, said Col. Kim Jong-chan, a spokesman at the South Korean Defense Ministry.

Cheolwon is located about 150 kilometers northeast to Seoul.

The ministry raised its security measure to the highest level in the area, said Kim, adding the South Korean military tightened roadblocks and traffic checkups in the area by establishing interim checkpoints.

Source: Xinhua