Taiwan celebrated its National Day holiday against the background of threats from China, which claims the self-governing island republic as its own territory.

Taiwanese President Lai Ching-te on Thursday vowed to resist Chinese annexation of his self-governing island nation as Taiwan celebrated its 113th National Day, provoking a harsh response from

President William Lai has pledged to uphold Taiwan's self-governing status in his most high-profile public address since taking office earlier this year. In a thinly-veiled reference to China's claim over the island, Lai said he would "uphold the commitment to resist annexation or encroachment upon our sovereignty."

Taiwan's Mainland Affairs Council, in a statement to Reuters on Thursday, said the four employees had been detained in China's Zhengzhou, home to a major Foxconn plant assembling Apple's iPhones, on suspicion of the equivalent of "breach of trust".

Chinese police have detained four workers of the Taiwanese iPhone maker, Foxconn, in circumstances Taipei has described as "strange". The employees were arrested in Zhengzhou in Henan province on "breach of trust" charges,

Chinese police have taken into custody four Taiwanese employees at Hon Hai Precision Industry Co., Apple Inc.’s main assembly partner, the latest in a spate of detentions that have rattled investor confidence in the country.