Five foreign military aircraft entered South Korea's air defense identification zone,
or KADIZ, without authorization on Tuesday morning.
Two of the jets were Chinese, while the other three were Russian.
The incident started after two Chinese H-6 aircraft entered the northwestern part of KADIZ at 6:44 AM and went in and out of KADIZ until later joined by two Tu-95 Russian bombers.
Then, they headed south.
The jets were flying close at an estimated three to six kilometers away from each other.
South Korea's Joint Chief of Staff said it was the first time Chinese and Russian planes have entered KADIZ simultaneously.
An early warning and control A-50 Russian aircraft then trespassed into the East Sea twice near Dokdo Island at around 9 AM for a total of seven minutes.
This had prompted the Air Force to scramble fighter jets and fire a total of 360 rounds of warning shots after the Russian pilot didn't respond to repeated audio warnings.
Officials said it's the first time the Air Force fired warning shots towards a foreign airplane due to airspace violation.
The Russian aircraft stayed in the KADIZ for a total of an hour and 33 minutes on Tuesday while the Chinese jets stayed there for a total of one hour and 25 minutes.
In response, Seoul's foreign and defense ministries summoned officials from China and Russia's embassies to severely protest against the violations.
"I should say Russia has never ever threat(threatened) the Republic of Korea. It’s very important."
"Did it have anything to do with John Bolton’s visit to South Korea?
Was North Korea involved in your actions today?
I have to mention one thing. Air recognition area is not airspace okay?"
Seoul's defense ministry said it has expressed regret to the officials and strongly requested for preventative measures.
Regarding the Russian aircraft violating South Korea's airspace the ministry said it sees it as a grave incident and if similar actions happen again, it warned Seoul will put all options on the table to respond accordingly.
Seoul's foreign ministry and the Blue House echoed the remarks.
The top office said director of national security, Chung Eui-yong sent a message to Nikolai Patrushev, the secretary of the Security Council of the Russian Federation.
Kim Ji-yeon, Arirang News.