Story highlights The unit was initially scheduled to be completed by 2019

It's a response to provocations by the North, Defense Ministry says

But it's a mistake, an analyst tells CNN

Seoul (CNN) South Korea is ratcheting up its rhetoric against Pyongyang with a new threat: Come at us, and we'll cut off the head of the snake.

The country is speeding up plans to set up what some call a "decapitation unit," a brigade specifically tasked with targeting North Korea's "wartime command," including leader Kim Jong Un, according to a South Korea Defense Ministry official.

The unit will be activated in the "event of war," the official said. Technically, South Korea and North Korea are still at war; they signed an armistice in 1953 but not a treaty.

The brigade was initially supposed to be ready in 2019, but the Defense Ministry now says it'll be established "by this year."

The move comes after a series of provocations by Pyongyang, including broadcasting images of Kim leading a combat drill targeting the South Korea's presidential residence, the Blue House.

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