Japan says 2 Russian fighters briefly entered its airspace

Japan's Defense Ministry said two Russian fighter jets briefly intruded into Japanese airspace Thursday off the northwestern tip of the island of Hokkaido, prompting Tokyo to lodge a protest.

Japanese air force jets scrambled after the intrusion by the two SU-27 jets off the coast of Rishiri island, which lasted less than a minute, ministry official Yoshihide Yoshida said.

Yoshida said it was not immediately known whether the airspace violation was intentional or accidental, but that it was "extremely problematic." The last intrusion by Russian jets in Japanese airspace was on Feb. 9, 2008, he said.

Japan's Foreign Ministry lodged a protest with the Russian Embassy in Tokyo.

Another ministry official who spoke on condition of anonymity said it was not immediately clear whether it was related to a government-sponsored rally held Thursday demanding that Moscow return a group of disputed islands off Hokkaido's eastern coast.

Prime Minister Shinzo Abe told the rally that he will do his utmost to resolve the dispute with Russia, which has kept the two nations from signing a peace treaty officially ending their hostilities in World War II.