North Korea sent what appeared to be trash-filled balloons toward South Korea on Wednesday, the South's military said, in the first such launch in 10 days.

The Joint Chiefs of Staff said the North launched the balloons, warning they may float toward Seoul and the surrounding Gyeonggi Province.

Since late May, the North has launched more than 5,000 balloons carrying trash on over 22 occasions in retaliation against anti-Pyongyang leaflets sent to the North by North Korean defectors and activists in South Korea. The last launch took place on Sept. 22.

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 on the border since July 21. It has refrained from directly shooting down the balloons, citing safety concerns. (Yonhap)