Story highlights

NEW: South Korea says it will restart propaganda broadcasts after hiatus of more than 10 years

The U.S.-led United Nations Command says North Korea planted mines on a DMZ patrol route

Two South Korean soldiers suffered severe leg injuries after stepping on the mines

Seoul, South Korea CNN  — 

South Korea says it will resume broadcasting propaganda messages over its heavily armed border with North Korea in retaliation for landmine blasts that wounded two of its soldiers.

The use of loudspeakers to blare government messages into North Korean territory is a form of psychological warfare that the South Korean Defense Ministry stopped more than a decade ago during a thaw in relations between the two sides.

A week after the landmine attack, the South restarted its propaganda broadcasts, infuriating North Korea, which has in the past threatened to blow up the huge speakers its neighbor set up at the demilitarized zone.

But the South Korean government is upset over the serious leg injuries suffered by two soldiers who stepped on landmines last week in the demilitarized zone, which is considered to be the most heavily fortified border in the world.

South Korea and the U.S.-led United Nations Command in Korea said Monday that the North Korean military planted the mines in the southern half of the zone along a route patrolled by South Korean troops.

Wounded soldiers forced to have amputations

One of the soldiers had to have part of each leg amputated, and the other had to have one foot removed at the ankle, the South Korean Defense Ministry said.

South Korea had demanded that Pyongyang apologize for the landmines and punish whoever is responsible for the attacks against its soldiers.

There was no immediate comment on the matter Monday in North Korean state media.

The South Korean Defense Ministry declined to specify when exactly the propaganda broadcasts would resume. It said sound from the the giant loudspeakers can travel about 24 kilometers (15 miles) at night and about 12 kilometers on weekdays.

Professor Lee Jung-hoon said we have not heard the end of the tensions.

“When we have the psychological warfare – the leaflets or the loudspeakers – basically the message is: the current leader is doing a very bad job, that their human rights are being violated, and that there’s a much better world outside that they should be aware of,” said Lee, an associate professor of international relations at Yonsei University in Seoul.

He said North Korea will not take kindly to criticism against Kim.

“For them Kim Jong Un, as his father and his father’s father was, is not just a political leader, he’s a deity figure,” he said. “For the leadership, just the fact that there’s the public condemnation and criticism of this godlike figure is just totally unacceptable.”

And North Korea, he said, will have some sort of reaction.

“Absolutely they will respond,” he said. “I can’t say in what way.”

U.N. Command condemns truce violations

The U.S.-led United Nations Command in Korea said that its investigation into the explosions found that the North’s Korean People’s Army had breached several parts of the armistice on the Korean Peninsula by planting landmines along a South Korean patrol route in the southern half of the demilitarized zone.

“The United Nations Command condemns these violations of the Armistice Agreement, and will call for a general officer level-dialog with the Korean People’s Army,” the U.N. Command statement said.

The U.N. Command, which monitors the armistice, said that the investigation had found that the wooden box landmines were recently planted, ruling out the possibility that they were old mines that might have been displaced by rain or other elements over the years.

Staff members from South Korea, the United States, New Zealand and Colombia took part in the investigation, the U.N. Command said.

Previous border tensions

The demilitarized zone has divided North and South Korea since the Korean War ended in 1953 with an armistice rather than a formal peace treaty. As a result, the two countries technically remain at war.

Tensions have flared in the past around sensitive points on their de facto border, including North Korea’s shelling of an island in 2010 that killed two South Korean marines.

Roughly 28,000 U.S. troops are based in South Korea.

CNN’s Kathy Novak reported from Seoul, and Jethro Mullen wrote from Hong Kong. CNN’s K.J. Kwon and journalist Hyoungjoo Choi contributed to this report.