South Korea said North Korea was flying balloons likely carrying trash across the border Tuesday for a second straight day, despite South Korea's threat to retaliate with anti-Pyongyang propaganda broadcasts at border areas.
 
The latest round of Cold War-style campaigns between the rival Koreas is flaring after North Korea recently signed a major defense deal with Russia that experts say could embolden the North to direct more provocations at its southern neighbor, reports AP.
 
South Korea's Joint Chiefs of Staff said the balloons were moving southeast on Tuesday night after crossing the border. It asked the South Korean public not to touch any North Korean balloons that fall to the ground and to report them to police or military authorities.
 
It's North Korea's sixth launch of balloons since late May. South Korea said North Korea floated rubbish-carrying balloons on Monday night, but no major damage was reported.
 
In a Tuesday speech marking a Korean War anniversary, South Korean President Yoon Suk Yeol called North Korea's balloon activities "a despicable and irrational provocation." He said South Korea will maintain a firm military readiness to repel any provocations by North Korea.
 
Later Tuesday, Yoon boarded a visiting U.S. aircraft carrier docked at a southeastern port and told American and South Korean troops there that the two countries' alliance is the world's greatest and can defeat any enemy. Yoon became the first sitting South Korean president to board a U.S. aircraft carrier since 1994.
 
South Korea's military said North Korea floated about 350 balloons in its Monday night campaign, and about 100 of them eventually landed in South Korean soil, mostly in Seoul and nearby areas. Seoul is about 40-50 kilometers (25-30 miles) away from the border. The military said the trash carried by the North Korean balloons were mostly papers and that no hazardous items were found.
 
In its earlier balloon launches, North Korea dropped manure, cigarette butts and waste batteries along with cloth scraps and waste papers in various parts of South Korea. No major damage was reported. In response, South Korea redeployed gigantic loudspeakers June 9 along the border for the first time in six years and briefly resumed anti-North Korean propaganda broadcasts.
 
Joint Chiefs of Staff spokesperson Lee Sung Joon told reporters Tuesday that the South Korean military is ready to turn on its border loudspeakers again. A written Joint Chiefs of Staff statement said officials would examine unspecified strategic operational circumstances and that broadcasts' resumption would depend on how North Korea acts.
 
Balloon launches and loudspeaker broadcasts were among psychological campaigns that the two Koreas specialized in during the Cold War. The rivals agreed to halt such activities in recent years, but have occasionally resumed them when animosities rekindled.
 
North Korea is highly sensitive to South Korean border broadcasts and civilian leafletting campaigns as it bans most of its 26 million people official access to foreign news.
 
South Korean leafleting campaigns by civilian activists, mostly North Korean defectors, include leaflets critical of North Korea's human rights violations and USB sticks containing South Korean TV dramas, while the past South Korean border broadcasts included K-pop songs, weather forecasts and outside news. In a statement Friday, Kim Yo Jong, the powerful sister of North Korean leader Kim Jong Un, called them "human scum" and "disgusting defectors."
 
South Korean officials maintain they don't restrict activists from flying leaflets to North Korea in line with a 2023 constitutional court ruling that struck down a law criminalizing such leafleting, calling it a violation of free speech.
 
Many experts say the North Korean balloon campaign is also likely designed to deepen a debate in South Korea over the civilian leafleting and trigger a broader internal divide.
 
Worries about North Korea intensified in mid-June, when North Korean leader Kim Jong Un and Russian President Vladimir Putin signed a deal requiring each country to provide aid if attacked and vowed to boost other cooperation. Observers say the accord represents the strongest connection between the two countries since the end of the Cold War.
 
The United States and its partners believe North Korea has been providing Russia with much-needed conventional arms for its war in Ukraine in return for military and economic assistance.
 
In his Korean War speech, Yoon described the Kim-Putin deal as "anachronistic." South Korea, the U.S. and Japan issued a joint statement Monday strongly condemning expanding military cooperation between Russia and North Korea.
 
The USS Theodore Roosevelt carrier and its strike group's arrival is meant to cope with North Korea's nuclear threats and its advancing military partnerships with Russia, South Korean officials said. Their deployment is also parts of a 2023 South Korea-U.S. deal meant to enhance "regular visibility" of U.S. strategic assets to the Korean Peninsula.
 
Yoon said the U.S. carrier is to leave the South Korean port Wednesday for a new trilateral South Korea-U.S.-Japan drill. The new multidomain "Freedom Edge" exercise is aimed at sharpening the countries' combined response in various areas of operation, including air, sea and cyberspace.
 
North Korea has previously reacted to such major U.S.-led drills with missile tests. On Monday, Kim Kang Il, the North's vice defense minister, called the the USS Theodore Roosevelt's deployment "the reckless option and action of the U.S."