South Korea's foreign ministry summoned on Monday the Russian ambassador in Seoul in protest over what it has called the dispatch of North Korean troops to Russia for deployment in Ukraine and pledged a joint international response.

The U.S. has around 28,500 soldiers stationed in South Korea. A report by the Chicago Council on Global Affairs shared with Newsweek this week found that over half of Americans (51 percent) back using American forces troops to defend South Korea if North Korea invaded.

SEOUL, South Korea (AP) — North Korea said Saturday it found the remains of a South Korean drone during a search in its capital, Pyongyang, claiming the drone proved the South’s military was behind the alleged drone infiltrations over the city’s skies earlier in the month.