A Chinese coast guard vessel sails in Japan’s contiguous zone around the Senkaku Islands, on Dec. 7, 2024. (Japan coast guard)

Chinese coast guard ships sailed near the Senkaku chain a record 355 times last year, as Beijing made good on its promise to increase its presence around the islands.

China topped the record it set the year before, when its vessels were spotted 352 times in the contiguous zone around the Senkakus, a territory administered by Japan, a spokesman with Japan’s coast guard said by phone Tuesday.

The contiguous zone is a 24-mile-wide band beyond the 12-mile territorial limit. Nations may exercise limited control in their contiguous zones, according to the United Nations.

The Senkakus, also claimed by China and Taiwan, include five uninhabited islets and three reefs 105 miles east of Taiwan and 254 miles west of Okinawa.

The vessels sailed within the Senkakus’ 12-mile territorial limit 39 times in 2024. The record is 52 times in 2013, the spokesman said.

Of the 2024 instances, 18 involved Chinese coast guard ships chasing Japanese fishing vessels, according to the spokesman.

Chinese vessels last intruded into territorial waters around the Senkakus on Dec. 6, according to a Japan coast guard news release that day. Four vessels that looked to be armed with deck-mounted machine guns were spotted and warned away with radio and electronic message boards.

The Japanese government has lodged numerous protests with Beijing over the incidents, including in September when four Chinese vessels armed with what appeared to be deck-mounted machine guns crossed the 12-mile limit.

China set another record in 2023 and 2024 for consecutive days sailing within the contiguous zone near the Senkakus. Vessels were spotted for 215 straight days from Dec. 22, 2023, to July 23, the spokesman said.

“The situation in the waters around the Senkakus is still severe and we cannot let our guard down,” Seishiro Sakamoto, commander of Japan’s 11th Regional Coast Guard, said in a statement Dec. 29, the day Chinese vessels broke the record for sightings around the Senkakus.

“We will respond resolutely while working closely with related authorities and take every measure to protect our territorial waters,” he said.

China has stepped up its presence around the Senkakus following a visit by President Xi Jinping in November 2023 to his country’s coast guard command in which he stated the necessity to “constantly strengthen” Beijing’s claim on the islands, Kyodo News reported at the time.

U.S. Ambassador to Japan Rahm Emanuel lambasted China’s plan to “keep ships in and around Japan’s Senkaku Islands for 365 consecutive days” in a January 2023 post on X.

The area around the Senkakus reportedly contains oil reserves and other resources, which has led to Chinese challenges to Japan’s claim over the islands since the 1970s, according to Japan’s Foreign Affairs Ministry.

The Pentagon identified China as an aggressive presence in the East and South China seas and a global “pacing challenge” in its 2022 National Defense Strategy.