South Korea said it fired warning shots at Russian aircraft after multiple planes entered South Korea’s airspace on Tuesday, in the first such incident between the two countries. South Korea’s Defense Ministry said three planes violated South Korean airspace off its east coast, before one of them entered the country’s territorial sky. Ministry officials said South Korea launched fighter jets and fired warning shots. Chinese military planes also intruded into South Korea’s aerial identification zone, according to ministry officials. The airspace that the Russian plane violated was above a group of South Korean-held islets halfway between South Korea and Japan that has been a source of territorial disputes between them. Russia is not a party in those disputes.