A top official involved in Taiwan's missile production was found dead in a hotel room on Saturday, even as China continued to carry out massive military exercises in the vicinity of the self-governed island, according to local media reports.

The army-owned institute where the official worked said he died of a heart attack.

Ouyang Li-hsing was vice president of the National Chung-Shan Institute of Science and Technology and had travelled to the south of the island for business, Taiwan's Central News Agency reported.

His death comes at a time when the island's government is trying to accelerate its own missile production as it faces an ever-increasing military threat from China.

In a statement posted on its website, the institute confirmed Ouyang was found unconscious at a hotel in Hengchun, Pingtung County on Saturday morning.

"Forensic examination found that the cause of death was myocardial infarction and angina pectoris," it said.

Ouyang assumed his position earlier this year and was tasked with supervising "the production of various types of missiles", CNA said.