SEOUL - South Korean warplanes fired hundreds of warning shots at a Russian military aircraft that entered South Korean airspace on Tuesday, defense officials said, while Russia denied violating any airspace and accused South Korean pilots of being reckless.

It was the first time a Russian military aircraft had violated South Korean airspace, an official at the South Korean Ministry of National Defense said in Seoul.

Two Russian bombers and two Chinese bombers entered the Korea Air Defense Identification Zone (KADIZ) together early on Tuesday, the defense ministry said.

A separate Russian early warning and control aircraft later twice violated South Korean airspace over Dokdo - an island that is occupied by South Korea and also claimed by Japan, which calls it Takeshima - just after 9 a.m. (midnight GMT Monday), according to the South Korean military.

Russia's defense ministry denied that its strategic bombers had violated South Korean airspace, the RIA news agency reported.

South Korean military planes crossed the path of Russian bombers and did not communicate with them, Russia's defense ministry said, according to RIA.

This was not the first time that South Korean pilots had interfered with a Russian military flight over neutral waters, the ministry said.

China's foreign ministry said South Korea's Air Defense Identification Zone was not territorial airspace and all countries enjoyed freedom of movement in it.

South Korea's top security adviser, Chung Eui-yong, lodged a strong objection with Nikolai Patrushev, secretary of the Security Council of Russia, asking the council to assess the incident and take appropriate action, South Korea's presidential office said.

"We take a very grave view of this situation and, if it is repeated, we will take even stronger action," Chung said, according to South Korea's presidential office. -Reuters