North Korea fires into South Korea, officials say

Gunfire was exchanged on the North Korean and South Korean border Friday, South Korean officials said.

North Korea troops fired two rounds near the town Chorwon, before South Korea returned with three "warning shots" and a message to desist by loudspeaker.

According to CNN there were no causalities. Also, it is unclear if the initial shots were deliberate, officials said.

The Korean borders are the most reinforced in the world, the BBC reported. They have thousands of troops stationed on both sides.