MANILA, Philippines (AP) — Taiwan’s foreign minister has flown to the Philippines as head of a high-level delegation of investors, two senior Philippine officials said Saturday, prompting a protest from China and a warning to Manila “not to play with fire.”

Relations between China and the Philippines have been strained as their coast guards and other forces spar in increasingly tense confrontations over the ownership of islands and fishing grounds in the disputed South China Sea. Taiwanese Foreign Minister Lin Chia-lung’s visit earlier this week to Manila and the Clark Freeport Zone, an industrial hub north of the capital, has exacerbated the tensions.

Philippine officials have publicly neither confirmed nor denied news reports of Lin’s visit, but two members of President Ferdinand Marco

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