North Korea's military warned Tuesday it would attack South Korea and turn it into "debris," in Pyongyang's latest response to what it says are confrontational activities by Seoul against the communist country.

The threat comes a day after military officers from the two Koreas held brief talks at the heavily fortified border, their second official contact since the North broke off inter-Korean relations in February.

The North threatened to cut off all ties if the "confrontational racket" continues, citing a South Korean general's recent threats to launch a pre-emptive strike against its nuclear sites and the refusal of civic activists in the South to heed Pyongyang's demands to cease distribution of propaganda leaflets critical of its leadership.

"The puppet authorities had better remember that the advanced pre-emptive strike of our own style will reduce everything opposed to the nation and reunification to debris, not just setting them on fire," the North's military said in a statement carried by the state-run Korean Central News Agency.

Relations between the two Koreas have been tense since South Korean President Lee Myung-bak's administration took office earlier this year pledging to get tough with Pyongyang.

Earlier this month, Gen. Kim Tae-young, chairman of South Korea's Joint Chiefs of Staff, told a parliamentary committee that his military was prepared to attack suspected nuclear sites in North Korea if the communist country attempts to use its atomic weapons on the South.

North Korea has demanded that South Korea stop activists from sending balloons carrying leaflets critical of the communist regime across the border, saying the flyers violate a 2004 inter-Korean accord banning propaganda warfare.

The South Korean government has stopped official propaganda but says it cannot prohibit activists from sending the leaflets, citing freedom of speech.

Defying Pyongyang's demands, South Korean activists on Monday sent helium balloons carrying 100,000 leaflets to the North. Some noted Kim's reported health troubles and called for the North Korean people to rise up against the authoritarian leader.

The North said it also was offended by recent comments by South Korean Defense Minister Lee Sang-hee about leader Kim Jong Il's health.

South Korean Defense Minister Lee Sang-hee told a news conference in Washington earlier this month that both the U.S. and South Korea believed Kim Jong Il remained in control, adding: "If we show him too much attention, then we might spoil him."

U.S. and South Korean officials say Kim suffered a stroke and underwent brain surgery in recent months, but the North has denied there is anything wrong with the 66-year-old leader.

The two countries remain technically at war because the 1950-53 Korean War ended with an armistice, not a peace treaty. The peninsula is divided by one of the world's most heavily fortified borders.