Taiwan's defense ministry issued an alert Tuesday saying China has launched a satellite and urging caution days before the island's elections.
Taiwan holds presidential and parliamentary elections Saturday that China has described as a choice between war and peace.
In English, the presidential alert sent to residents' mobile phones cautioned there was a missile flyover.
The alerts went off in the middle of an international news conference by Taiwanese Foreign Minister Joseph Wu.
He clarified it was a satellite launch, told journalists not to worry, and proceeded with the news conference.
China views Taiwan, which is about 160 kilometers (100 miles) off China's east coast, as a renegade province that must come under its control.