A Russian air force bomber briefly violated Japanese airspace over an uninhabited island just south of Tokyo on Saturday, the Foreign Ministry said.

The three-minute flyby over Sofugan in the Izu island chain by a Tupolev 95 ended following warnings by Japanese air force fighter jets, said Foreign Ministry official Kotaro Otsuki.

The ministry immediately lodged a protest with the Russian Embassy in Tokyo and demanded an explanation, Otsuki said.

A switchboard operator at the embassy said no one was available to comment Saturday.

Japan's navy scrambled 22 fighter jets, including F-15s, and two airborne warning and control aircraft known as AWACs, a Defense Ministry official said on condition of anonymity, citing protocol.

Japan held a rally Thursday to demand the return of a disputed island chain that Russia seized in the closing days of World War II. The capture of the four islands, called the Kurils in Russia and the Northern Territories in Japan, kept the two countries from signing a peace treaty.

Japan holds a rally every Feb. 7, the anniversary of an 1855 Japan-Russian friendship treaty that gave Japan possession of the islands.

Otsuki said he didn't know if Saturday's flyby was related to the rally Thursday. He said Russia last violated Japanese airspace in January 2006 near Rebun Island off Japan's northern main island of Hokkaido — and close to the disputed northern islands.

Sofugan, which lies on the southernmost tip of the Izu island group, is about 650 kilometers (400 miles) south of Tokyo.