A North Korean balloon crossed over the border into ROK airspace on Sunday, according to South Korea’s defense ministry, days after a suspected Chinese spy balloon stirred up a major controversy by floating over the mainland U.S.

The South Korean military “took measures” against the balloon but concluded the operation after determining that it did not pose a security threat, the defense ministry told NK News. The ministry did not confirm the size or type of balloon or where the military detected it.

South Korean broadcaster KBS, citing a high-level military source, reported that a front-line unit detected