Tokyo says China coast guard vessel 1305, seen here in August 2019, appeared to be armed with a deck-mounted machine gun when it entered Japanese territory near the Senkaku Islands, Thursday, March 16, 2023. (Japanese coast guard)

CAMP FOSTER, Okinawa — Tokyo lodged a series of diplomatic protests with Beijing last week after China sent several coast guard vessels, including one armed with a deck-mounted machine gun, near its islets in the East China Sea.

Four Chinese coast guard ships passed the 12-mile territorial limit around the Senkakus eight times in three separate incidents on Wednesday, Thursday and Friday, a Japanese coast guard spokesman told Stars and Stripes by phone Monday. Each ship stayed in those waters for less than 24 hours and left without incident.

Japan’s Ministry of Foreign Affairs complained to the Chinese Embassy in Japan and to officials in Beijing on all three days, a ministry spokesman said by phone Monday.

“We asked them to leave the area,” the spokesman said. Some government officials in Japan are required to speak to the media only on condition of anonymity.

A pair of Chinese coast guard vessels following a Japanese yacht approached Minamikojima Island in the Senkakus from the east-southeast and entered the 12-mile limit just before 9 a.m. Wednesday, according to the coast guard spokesman. The ships, which appeared to be unarmed, remained until 3:49 p.m. and 3:55 p.m., respectively, then departed to the south.

Four China coast guard ships on Thursday followed a pair of Japanese fishing boats into Japan’s territory near the Senkakus between 6:40 a.m. and 6:55 a.m., the spokesman said. Three of the vessels entered from the south of Minamikojima, while one entered from the south of Uotsuri Island, about three miles away.

One of those ships appeared to be armed with a deck-mounted machine gun, the coast guard spokesman said.

Those vessels departed Japan’s territorial waters between 11:18 p.m. and 11:34 p.m., the spokesman said. Three left to the east of Minamikojima while one departed from the south-southeast of Kuba Island, 13 miles northeast of Uotsuri.

Then on Friday, two Chinese coast guard vessels, including the one armed with a deck-mounted machine gun, reentered Japan’s 12-mile limit while shadowing two Japanese fishing boats, the spokesman said. They entered from the southwest of Taisho Island between 4:24 a.m. and 4:49 a.m. and departed to the south of Taisho at 8:27 p.m. and 8:58 p.m., he said.

In each case, the Chinese ships were met by a larger contingent of Japanese coast guard vessels, according to the coast guard spokesman, who declined to provide the exact number. They positioned themselves between the Chinese and Japanese vessels to prevent contact and warned the Chinese to leave the area.

The three incidents bring the number of Chinese intrusions into Japan’s territorial waters this year to nine, the spokesman said. The last incident occurred Feb. 24.

The Senkakus are 105 miles east of Taiwan. The islets, whose surface area amounts to about 2½ square miles, are also claimed by China and Taiwan. The surrounding area is said to contain a wealth of natural resources, including fish, oil and natural gas.