South Korean President Park Geun-hye issues a statement to the nation from the presidential office in Seoul. (Photo by Jeon Heon-Kyun/EPA)

Fragile relations between North and South Korea were once again rattled on Saturday night when the North fired several artillery rounds into the sea near a disputed maritime border, alarming nearby residents in the South.

The shots were heard from the island of Baengnyeong, which is located near the Northern Limit Line, the disputed border in the Yellow Sea. A South Korean Defense Ministry official told Reuters that the rounds were likely fired as part of a military exercise.

Tensions have been escalating between the North and South since Pyongyang's nuclear test in January and a long-range rocket launch two weeks ago. South Korean president Park Geun-hye's strong condemnation of the acts has sparked an escalating war of words. In the latest barrage of insults, North Korea's state news agency KCNA called Park a "tailless old insane bitch," though the agency softened the insult to "dog" in its English translation. They also called her a "senile granny."

KCNA has previously suggested that Park lives on the "groin of her American boss," and described her as a "confrontation maniac just like a rabid dog always keen on biting others."

Watch the VICE News documentary Launching Balloons into North Korea: Propaganda Over Pyongyang:

Park said the latest nuclear test, which Pyongyang claims was a hydrogen bomb, was "not only a grave provocation to our national security but also a threat to our future." Speaking at an emergency national security meeting in January, she also called the test "a threat to our future… and a strong challenge to international peace and stability."

Seoul also vowed to take "all necessary measures," which may include additional sanctions by the UN Security Council to ensure that "the North will pay the price for the nuclear test."

Barbs out of Pyongyang are infamous for their creativity and ability to pack a punch. Park hasn't been the only target of North Korea's scathing personal attacks. KCNA described former US secretary of state and presidential hopeful Hillary Clinton as a "funny lady" who looks like "a primary schoolgirl." Current Secretary of State John Kerry didn't have any better luck; Pyongyang deemed him "a wolf with a hideous lantern jaw."

When North Korea's internet connection became unstable following their cyberattack on Sony Pictures in 2014, KCNA resorted to a racial slur, comparing President Barack Obama to "a monkey in a tropical forest." Obama has also been dubbed "the world's sole juvenile delinquent."

In 2012, KCNA published a cartoon depicting the former South Korean President Lee Myung-Bak with the caption, "The dirty hairy body of rat-like Myung-Bak is being stabbed with bayonets. One is right in his neck and the heart has already burst open. Blood is flowing out of its filthy bottom hole."