Objects believed to be trash are spotted falling from a balloon sent by North Korea over Mount. Nam in Seoul, Oct. 4. Korea Times photo by Shim Hyun-chul

North Korea floated trash balloons toward South Korea early Tuesday, the South's military said, in what marked the second straight day of such provocation.

The Joint Chiefs of Staff raised the possibility of the balloons floating toward northern Gyeonggi Province and other parts of the Seoul metropolitan area, advising citizens not to touch them and to be careful of balloons potentially dropping.

Since late May, the North has sent more than 5,000 balloons across the border toward South Korea. In its previous launch on Monday, the North sent some 120 balloons carrying trash.

South Korea's military has vowed to take "stern" military measures should North Korea "cross the line" with its ongoing trash balloon campaign or inflict serious damage to the South Korean people.

In response to the balloon launches, the South's military has been blasting daily anti-North Korean propaganda broadcasts through loudspeakers along the border since July 21. It has refrained from directly shooting down the balloons, citing safety concerns. (Yonhap)