Air Force General Shen Yi-ming, who was Taiwan's chief of general staff, was killed after a helicopter carrying 13 people crash-landed into a mountain on Thursday, according to the defense ministry.
Taiwan's official Central News Agency also confirmed General Shen's death.
At least eight people have been killed in the helicopter crash, according to some reports.
The helicopter made an emergency landing in the mountains near Taipei after taking off on a routine mission to visit soldiers in the northeast Yilan country ahead of the lunar new year.
Rescue operation underway
Air force commander-in-chief Hsiung Hou-chi told a news conference in Taipei that it remains uncertain what caused the incident.
"The search and rescue operation continues... We are investigating whether (the cause) was environmental or mechanical... the aircraft's condition is not ideal," Hsiung told reporters.
"We hope everyone can be safe and we should know the results this afternoon," he added.
Taiwan is a de facto sovereign nation since the end of a civil war in 1949. China claims Taiwan as part of its territory and has threatened the use of force to bring the country back under its control.
Read more: Can Taiwan counter China's 'diplomatic aggression'?
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shs, ed/aw (AFP, Reuters, dpa, AP)