Watch CBSN Live

In latest PR salvo, North Korea says it approved plans for nuclear attack on U.S.

Updated 11:22 PM ET

(CBS News) THE PENTAGON - There were more threatening words -- and actions -- Wednesday from North Korea.

The country says it's leadership has approved plans for a nuclear strike on the United States. They have also put up a roadblock at a border crossing, stopping South Korean workers and supplies from reaching the Kaesong industrial park, where textiles and electronics are made. The Associated Press reported that the South Korean workers were again turned away from the Kaesong factories on Thursday morning.

Latest U.S. message to N. Korea: Missile defense system sent to Guam
North Korea blocks South Koreans from joint Kaesong industrial complex
John Kerry: North Korea has "option" to peacefully join global community

The industrial park at Kaesong was the one slender thread of evidence that two countries at each others' throats could still do business. Now, in what one U.S. official called "the provocation of the day," this last point of contact between the two countries has been cut off. It's added to North Korea's warlike posturing, which Defense Secretary Chuck Hagel said cannot be ignored.

"It only takes being wrong once, and I don't want to be the secretary of defense who was wrong once. So we will continue to take these threats seriously," Hagel said.

Defense Secretary Chuck Hagel answers questions as he speaks at the National Defense University at Fort McNair in Washington, Wednesday, April 3, 2013. AP Photo/Manuel Balce Ceneta

Last week, North Korea's dictator Kim Jong Un ordered his missile units to prepare for attacks on the U.S. itself in retaliation for an annual exercise involving American and South Korean forces.

"Some of the actions they've taken over the last few weeks present a real and clear danger and threat to the interests, certainly of our allies," Hagel said.

The Pentagon announced Wednesday it is sending a battery of air defense missiles to the Pacific island of Guam, which recently served as a base for B-52 bombers that flew over South Korea as part of that annual exercise. Next week the exercise will include an amphibious landing and live fire drills by U.S. Marines.

There are still no troop movements to indicate North Korea is about to attack either the U.S. or South Korea. But with all this harsh rhetoric, there is concern a minor incident, such as an exchange of gunfire over disputed fishing waters, could quickly spin out of control.

Map of the North Korea/South Korea border, including Kaesong.
Map of the North Korea/South Korea border, including Kaesong. CBS News
View CBS News In
CBS News App Open
Chrome Safari Continue
Be the first to know
Get browser notifications for breaking news, live events, and exclusive reporting.