A J-15 carrier-borne fighter jet takes off from the flight deck of the aircraft carrier Liaoning during a maritime training exercise on July 1, 2017. The Chinese aircraft carrier Liaoning and its carrier strike group carried out realistic training in an undisclosed sea area on July 1, 2017. (eng.chinamil.com.cn/Photo by Li Tang)

The aircraft carrier Liaoning of the Chinese People's Liberation Army (PLA) Navy reportedly hosted about 130 aircraft sorties in four days after it entered the West Pacific for far sea drills last week, more than twice as intensive as the exercises held in the same region in May, displaying the carrier's high level of combat readiness, analysts said on Thursday.

Japan's Maritime Self-Defense Force spotted the PLA Navy's Liaoning aircraft carrier group, including the Type 055 large destroyers Anshan and Wuxi, the Type 052D destroyer Chengdu, the Type 054A frigate Zaozhuang and the Type 901 comprehensive replenishment ship Hulunhu, sailing in the West Pacific south of Japan around Okidaitojima island and Kitadaitojima island from Saturday to Tuesday, Japan's Ministry of Defense Joint Staff said in a press release on Wednesday.

During this period, the Liaoning hosted about 60 sorties of carrier-based fighter jets and about 70 sorties of carrier-based helicopters, or about 130 aircraft sorties in total, read the Japanese press release. According to photos attached to the release, J-15 fighter jets from the aircraft carrier Liaoning carried air-to-air missiles in their sorties.

By comparison, the Liaoning hosted more than 300 fighter jet and helicopter sorties in some 20 days in the far sea exercises in the West Pacific in May, and it was deemed by observers as the most sortie-intensive exercise by the Chinese carrier in the region at the time.

This means that the aircraft sorties during the four days were more than twice as intensive as the exercise in May, and if the Liaoning keeps training at this rate, this voyage will set a record, a Chinese military expert told the Global Times on Thursday, requesting anonymity.

By ramping up aircraft sorties in the drills, the Liaoning is increasing its capabilities and demonstrating a high level of combat readiness, the expert said.

Japan reported details of the Liaoning's exercises, wanting to hype the "China threat" theory, but it also let the outside world know how capable the PLA Navy is more objectively, the expert said.

The PLA Navy flotilla led by the aircraft carrier Liaoning sailed from the East China Sea via the Miyako Strait into the West Pacific on December 16, Japan's Ministry of Defense Joint Staff said at the time.

Before this, Japan also reported that a PLA Navy flotilla consisting of the Type 055 large destroyer Lhasa, the Type 052D destroyer Kaifeng and the Type 903A replenishment ship Taihu sailed from the East China Sea through the Osumi Strait into the West Pacific from December 13 to 14, but those ships were not seen around the aircraft carrier Liaoning from Saturday to Tuesday.

This might indicate that this is a separate flotilla from the Liaoning aircraft carrier group on another far sea exercise, possibly making a circumnavigation sail around Japan, observers said.

In another development, China and Russia started the week-long Joint Sea 2022 naval exercise in the East China Sea on Wednesday.

While the exercises are not targeted at any third party, they serve as deterrence against those who make provocations, analysts said.