The saber rattling in the Korean Peninsula escalated Friday as the North threatened military action if South Korea does not stop blaring propaganda from speakers across the border by Saturday.

Reporting from Seoul, Haeryun Kang tells our Newscast unit that Pyongyang has put its frontline troops on a "semi-war state"

Haeryun reports:

"North Korea's familiar rhetoric is ratcheting up new tensions. It came one day after the two sides exchanged fire at the border. No casualties were reported, but South Korean president Park Geun-hye convened an emergency meeting and ordered the military to deal 'resolutely' with any provocation.

"Pyongyang warned it will take military action if the South's propaganda loudspeakers aren't removed by Saturday at 5 p.m. Seoul raised military readiness to the highest level.

"Last week, North and South resumed broadcasts for the first time in 11 years. This was sparked by the land mines that maimed two South Korean soldiers earlier this month. Despite Seoul's accusations, Pyongyang denies having planted the mines."

On Twitter Haeryun points out that there is one small complication in all of this: North Korea recently pushed back all its clocks by 30 minutes. So, South Korea is not sure if the North's deadline means 5 p.m. or 5:30 p.m.

As we've reported, the latest provocations escalated into an exchange of artillery fire for the first time in five years.

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