(Bloomberg) -- Two Russian military planes flew into South Korea’s Air Defense Identification Zone four times on Friday, the Korean military said.

The South Korean air force scrambled fighter jets and issued a warning after identifying two Russian planes coming from the country’s East Sea around 1:41 p.m. on Friday, according to a text message sent to reporters from the Korean Joint Chiefs of Staff. The Russian planes entered the zone three more times during Friday afternoon, passing over the Korea’s east coast and waters near the country’s southernmost island of Jeju.

South Korea’s defense ministry complained about the infringement on the Korean defense zone at a meeting with Andrey P. Falileev, a Russian colonel in Seoul, Yonhap News Agency reported on Saturday, citing the ministry. The Russian planes were said to be TU-95 long-range strategic bombers, Yonhap reported without citing anyone.

Russian planes entered the defense zone several times this year but it is the first time they have done it multiple times in a day, Yonhap reported, citing an unidentified official at Korean Joint Chiefs of Staff. A Chinese military plan flew into the zone three times in 2018, claiming it was a regular drill.

To contact the reporters on this story: Heejin Kim in Seoul at hkim579@bloomberg.net;Kanga Kong in Seoul at kkong50@bloomberg.net

To contact the editors responsible for this story: Stanley James at sjames8@bloomberg.net, John McCluskey

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