Russia's Ministry of Defense on Tuesday denied that its strategic bombers had violated South Korean air space and accused South Korean jets of carrying out dangerous maneuvers that threatened its aircraft, the RIA news agency reported.

Defense officials in Seoul said earlier that the South Korean air force had fired 360 rounds of warning shots at a Russian military aircraft that illegally entered South Korean airspace on Tuesday.

Three Russian military planes — two Tu-95 bombers and one A-50 airborne early warning and control aircraft — initially entered South Korea's air defense identification zone off its east coast before the A-50 entered the country's territorial sky, the South's Defense Ministry said.

South Korean fighter jets then scrambled to the area to fire 10 flares and 80 rounds from machine guns as warning shots, a ministry official said, requesting anonymity due to department rules.

The Russian reconnaissance aircraft left the area but it returned and violated the South Korean airspace again later Tuesday, the ministry official said. He said the South Korean fighter jets fired 10 flares and 280 rounds from machine guns as warning shots again. Each time, the Russian plane didn't return fire, the official said.

But Russia's defense ministry denied that and said South Korean pilots had not communicated with the Russian bombers.

South Korean officials said it was the first time a Russian military plane violated South Korean airspace. But the Russian Defense Ministry said it was not the first time that South Korean pilots had interfered with a Russian military flight over neutral waters.

The former Soviet Union supported North Korea and provided the country with weapons during the 1950-53 Korean War, which killed millions. In 1983, a Soviet air force fighter jet fired an air-to-air missile at a South Korean passenger plane that strayed into Soviet territory, killing all 269 people on board. Relations between Seoul and Moscow gradually improved, and they established diplomatic ties in 1990, a year before the breakup of the Soviet Union.

The airspace the Russian warplane violated Tuesday was above a group of South Korean-held islets roughly halfway between South Korea and Japan that has been a source of territorial disputes between them. Russia isn't a party in those disputes.

The three Russian planes had entered the South Korean air defense identification zone with two Chinese bombers. But it wasn't immediately known whether the two countries deliberately did so, according to the South Korean official.

Before their joint flights with the Russian planes, the Chinese warplanes entered South Korea's air defense identification zone off its southwest coast earlier Tuesday, according to the South Korean official. Chinese planes have occasionally entered South Korea's air defense identification zone in recent years.

South Korea's Defense Ministry said it plans to summon Russian and Chinese Embassy officials later Tuesday to register formal protests.