China has begun dispatching surveillance vessels off the coast of Hawaii in response to the Navy's monitoring activities of disputed islands in the South China Sea, according to the Taiwan newspaper Want China Times.

The purported surveillance comes on the heels of raised tensions between China and the United States late last month. A Navy P-8A Poseidon surveillance plane was flying over the Spratly Islands near the Philippines and Malaysia when a Chinese radio dispatcher warned it several times to depart the airspace.

China has been enlarging some of the uninhabited atolls by dredging up sand from the sea bottom, claiming it has sovereignty of the islands and the airspace above.

U.S. officials say China has placed artillery on the expanded islands and have called for its removal.

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I'm not going to speculate about a vague news report on Chinese surveillance ship intentions," Capt. Darryn James, U.S. Pacific Fleet chief spokesperson in Honolulu, said in response to a Stars and Stripes query whether Chinese ships have been detected near Hawaii.

"I will say that it is a fundamental right of all nations for military ships and aircraft to operate in international waters and airspace in accordance with well-established international law. The U.S. Navy closely monitors all activity in the Pacific, so regardless of what the Chinese navy does, we won't be caught surprised."

China raised eyebrows during the Rim of the Pacific naval exercise in Hawaii last July. Invited for the first time, it brought two ships but also sent a surveillance ship that monitored the multilateral exercise from afar.

At the time, U.S. Pacific Command head Adm. Samuel Locklear III described the spying "a little odd" but essentially "good news" because it indicated an acceptance by the Chinese "that military operations and survey operations in another country's [maritime zones] are within international law and are acceptable, and this is a fundamental right that nations have."

Locklear's new replacement, Adm. Harry Harris, took a harder-edged tack in regard to China's sweeping claims of islands in the South China Sea, calling them "preposterous" during his change-of-command ceremony last week.

Late last month, China released a defense white paper that pledged to shift its navy's focus to "open seas protection" and away from strictly defending waters off the mainland.

"China is faced with complicated threats and challenges in the oceans and needs a navy that can guard its sovereignty and perform multifaceted military missions," Senior Col. Wang Jin, with China's People's Liberation Army, told a news conference May 26, according to the South China Morning Post in Hong Kong.

China's official news agency, Xinhua, summarized the shift in strategy for China's military as "active defense."