Japan was forced to scramble combat fighters jets on Thursday after two Russian fighter jets briefly entered Japan’s airspace near the Hokkaido, according to Japan’s Foreign Ministry.
One ministry official was quoted as saying it was the first intrusion of its kind in at least five years, according to NBC News.
Former Japanese Prime Minister Yoshiro Mori is slated to travel to Moscow later in February to discuss territory claims with Russia.
Thursday marked Japan’s “Northern Territories Day,” a day on which rallies are traditionally held calling for the return of the disputed islands located off of Hokkaido.
Russian PM Dmitry Medvedev visited the island chain back in July, sparking protests from the city of Tokyo.
Medvedev’s trip to the islands located in Russia’s Far East caused Japan’s Ministry of Foreign Affairs to formally lodge a complaint.
The dispute with Russia over the island can be traced all the way back to World War Two.
At the end of that way, Soviet soldiers captured the islands and the dispute has been heated ever since.