A senior Taiwanese defence official responsible for missile production was found dead on Saturday morning in a hotel room amid rising tensions with China.
Ou Yang Li-hsing, deputy head of the military-owned National Chung-Shan Institute of Science and Technology, died in a hotel room in southern Taiwan, the official Central News Agency reported.
Authorities said Ou Yang, 57, died of a heart attack and the hotel room showed no sign of any "intrusion".
His family said he had a history of heart disease and had a cardiac stent, according to the report.
Ou Yang was on a business trip to the southern county of Pingtung, CNA said, adding that he had assumed the post early this year to supervise various missile production projects.
The military-owned body is working to more than double its yearly missile production capacity to close to 500 this year, as the island boosts its combat power amid what it sees as China's growing military threat.
As China continues to carry out military drills Taiwan's defence ministry dispatched aircraft and ships and deployed land-based missile systems.
Multiple Chinese vessels and aircraft crossed the Taiwan Strait median line on Friday morning the defence ministry said, which described China's military activities as highly provocative.
Taiwan's military will prepare combat readiness but will not ask for a war, the defence ministry added.
China has been carrying out unprecedented military drills following the visit of US House Speaker Nancy Pelosi's visit to Taiwan.
Its state broadcaster said the military exercises, which began on Thursday - the day after Ms Pelosi left Taiwan - and are set to end on Sunday, would be the largest conducted by China in the Taiwan Strait. The exercises have involved live fire on the waters and in the airspace around the island.
Ms Pelosi praised Taiwan on Friday, pledged US solidarity and said her trip through Asia, was never about changing the regional status quo.
She was with a congressional delegation in Japan on the last stage of an Asian trip that included a brief and unannounced stop in Taiwan, the self-ruled island that Beijing considers its own - and prompted an infuriated China to hold its live-fire drills in waters around Taiwan, with five missiles landing in Japan's exclusive economic zone(EEZ).
Her stop in Taiwan, the highest-level visit by a US official in 25 years, came as Tokyo, one of Washington's closest allies, has become increasingly alarmed about China's growing might in the Indo-Pacific and the possibility that Beijing could take military action against Taiwan.
"We have said from the start that our representation here is not about changing the status quo in Taiwan or the region," she told a news conference after meeting with Japanese Prime Minister Fumio Kishida.
"The Chinese government is not pleased that our friendship with Taiwan is a strong one," she added.
"It is bipartisan in the House and in the Senate, overwhelming support for peace and the status quo in Taiwan."