The potential for China to use balloons for spying became a global issue in February 2023 when the United States shot down what it said was a Chinese surveillance balloon. China said the balloon was a civilian craft that accidentally drifted astray.
Taiwan is on high alert for Chinese activities, both military and political, ahead of Jan. 13 presidential and parliamentary elections. China claims the island as its own territory.
Taiwan's defence ministry has since last month reported several instances of Chinese balloons flying over the sensitive Taiwan Strait, then crossing airspace to the island's north before vanishing.
On Wednesday, giving its daily update for Chinese military activities over the past 24 hours, the ministry said it had detected four balloons flying over the strait, three of which flew across the centre of the island.
It said the three flew 105 nautical miles (194 km), 160 nautical miles and 159 nautical miles respectively to the southwest of Ching Chuan Kang, home to an important Taiwan air force base.
The balloons then disappeared at various points, the ministry added.
It did not say what it thought the balloons were used for, but the ministry has previously said it believed they were mostly for weather monitoring.
(Reporting by Ben Blanchard; Editing by Jacqueline Wong and Jamie Freed)
