Photo/Illutration A Maritime Self-Defense Force P-1 patrol aircraft launches flares in a fleet review ceremony in October 2015. The aircraft that released flares to warn off an intruding Russian aircraft on Sept. 23 was a different model. (Asahi Shimbun file photo)

The Defense Ministry and the Self-Defense Forces are condemning a Russian IL-38 patrol aircraft's intrusion into Japanese airspace three times on Sept. 23 as “deliberate acts of intimidation.”

Defense Minister Minoru Kihara told reporters at a news conference on Sept. 24 that “it is not wrong to deem them as intimidation,” regarding the overflights of a Russian aircraft.

He also noted that an Air Self-Defense Force aircraft acted appropriately in firing flares for the first time as a warning to the Russian aircraft during its third intrusion.

A senior Defense Ministry official also said that he believes the Russian intrusion was deliberate and not a mistake.

According to the Joint Staff Office, the Russian patrol aircraft arrived at the site at around 12:50 p.m. on Sept. 23.

It continued to fly in a grid pattern for about five hours. During the five hours, at about 1:03, 3:31 and 3:42 p.m., it entered Japanese airspace for 30 seconds to about a minute, respectively.

Several senior ministry staffers believe that the Russian aircraft was conducting anti-submarine warfare training. The Joint Staff Office said the bomb bay doors of the aircraft were open.

The airplane usually drops sonobuoys, a device to collect sounds in a water, from its bomb bay.

Akira Saito, chief of staff of the Maritime Self-Defense Force, said in another news conference on Sept. 24 that the Russian patrol aircraft is believed to usually be engaged in search activities.

The patrol aircraft flew for about 10 hours. Sources close to the SDF said that the aircraft is believed to have flown for its maximum flight duration, including the round trip from its Russian base.

Senior Defense Ministry officials expressed their concern, saying, “It is unprecedented that Russia conducted training close to Japan and entered Japanese territorial airspace as many as three times.”

In August, a Chinese military aircraft for the first time intruded into Japanese airspace off the coast of Nagasaki Prefecture. In response, the Defense Ministry and the SDF have been strengthening their vigilance.