SEOUL

Russia has expressed “deep regret” that one of its warplanes accidentally intruded into South Korean airspace this week, according to South Korea’s presidential office Wednesday.

A day earlier, a Russian A-50 early warning and control aircraft twice entered South Korean airspace, prompting the South to scramble fighter jets and fire hundreds of warning shots.

Seoul later threatened to take stronger counteraction if there is a repeat of the incident, which was the first of its kind in the South, although there have been unannounced entries into the country’s air defense identification zone – including by Russian and Chinese bombers on Tuesday.

Based on Wednesday’s government statement from Seoul, Russia has admitted it was a mistake that happened during joint air drills with China.

“Russia said its Defense Ministry will immediately launch a probe and take necessary steps,” presidential office spokesperson Yoon Do-han was quoted as telling reporters by local news agency Yonhap.

The official was referring to a message sent by a Russian military attache to the South’s Defense Ministry.

"Moscow said if the aircraft flew according to an initially planned route, this incident would not have occurred," Yoon added.