A North Korean patrol ship crossed a maritime border with the South multiple times last night, South Korea's defense ministry says. It finally ended up in North Korean waters—but not until the South had broadcast 10 warnings, Yonhap News reports. The border crossing may have been "part of military drills or an inspection" of the Seoul's military, a defense spokesman for the South says. With the South beginning military drills with the US, "it is believed that (the North Korean ship) intended to test the South Korean military." Fire wasn't exchanged, the Wall Street Journal reports.
The North disagrees with the South on the location of the sea border known as the Northern Limit Line. Recently, ties appear to have improved somewhat between the two countries; reunions of divided families are currently in progress. The South doesn't always announce run-ins with Pyongyang's military, but it mentioned this one given recent heightened interest in the countries' relationship, the spokesman says. The border violation is the first reported this year; there were three such incidents last year, the spokesman adds. (Read more North Korea stories.)