The deputy head of Taiwan defence ministry's research and development unit was found dead on Saturday morning in a hotel room, according to the official Central News Agency.
Ou Yang Li-hsing, deputy head of the military-owned National Chung-Shan Institute of Science and Technology, was found dead in a hotel room in southern Taiwan on Saturday morning, CNA reported.
Authorities said 57-year-old Ou Yang died of a heart attack and the hotel room showed no sign of any 'intrusion', CNA said. 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, Reuters reported.
Taiwan's military said it observed "multiple" Chinese planes and ships operating in the Taiwan Strait on Saturday, believing them to be simulating an attack on the self-ruled democracy's main island.
Taipei's forces "detected multiple batches of Communist planes and ships conducting activities around the Taiwan Strait, some of which crossed the median line. They were judged to be conducting a simulation of an attack on Taiwan's main island," the defence ministry said in a statement.
Taiwan's defence ministry said that it had fired flares late on Friday to warn away seven drones flying over its outlying Kinmen Islands and to warn unidentified aircraft flying over its outlying Matsu Islands.
The ministry said troops were on high alert in both areas, which lie just off the coast of mainland China, after Beijing launched large-scale military drills this week in response to a visit to Taiwan by US House of Representatives Speaker Nancy Pelosi.
In a bid to show just how close China's forces have been getting to Taiwan's shores, Beijing's military overnight released a video of an air force pilot filming the island's coastline and mountains from his cockpit.
Beijing also said they would hold a live-fire drill in a southern part of the Yellow Sea -- located between China and the Korean peninsula -- from Saturday until 15 August, reports AFP.
China's state broadcaster, CCTV, has reported that Chinese missiles have flown directly over Taiwan during the exercises -- a major escalation if confirmed.
Taipei has remained defiant, insisting it would not be cowed by its "evil neighbour".
'Punishing the whole world'
The scale and intensity of China's drills have triggered outrage in the United States and other democracies, with the White House summoning China's ambassador to Washington on Friday to rebuke him over Beijing's actions.
Beijing's decision to withdraw from hard-won cooperation on climate change has now sparked wider fears about the future of the planet.
"It's obviously worrying and raises concerns," Alden Meyer, a senior associate at E3G, a climate-focused think tank, told AFP.
It's "impossible to address the climate emergency if the world's number one and number two economies and number one and number two emitters are not taking action," he said.
"And it's always preferable that they do that in a collaborative way."
National Security Council spokesman John Kirby told reporters in Washington the decision was "fundamentally irresponsible."
"They're actually punishing the whole world, because the climate crisis doesn't recognize geographic boundaries and borders," Kirby said.
"The world's largest emitter now is refusing to engage on critical steps necessary to combat the climate crisis."
UN Secretary-General Antonio Guterres warned the two superpowers must continue to work together -- for the world's sake.
"For the secretary-general, there is no way to solve the most pressing problems of all the world without an effective dialogue and cooperation between the two countries," his spokesman Stephane Dujarric said.
'The new normal'
But with tensions over Taiwan having risen to their highest level in nearly 30 years with an elevated risk of military conflict, experts told AFP the latest downturn in relations between the two superpowers could be deep and long-lasting.
"The relationship is in a very bad place right now," said Bonnie Glaser, a China expert at the German Marshall Fund.
The suspension Friday of bilateral military and maritime dialogue while China continues its military exercises was "particularly worrisome," she said.
"We don't know what else they will do," she said. "We just don't know if this is just a temporary thing."
John Culver, a former CIA Asia analyst, said in a discussion hosted by the Center for Strategic and International Studies that Beijing's main purpose with its military exercises was to change that status quo.
"I think that this is the new normal," Culver said. "The Chinese want to show... that a line has been crossed by the speaker's visit."