Taiwan slowed the mobile internet in a large swathe of the central part of the island on Monday for the first time during annual war games, simulating communication disruption in the event of a Chinese attack or natural disaster.
Democratically governed Taiwan, which China claims as its own territory, has long lived with the threat of a Chinese invasion and holds air raid drills along with its war games every year, clearing people from the streets for 30 minutes.
During the internet "throttling" drill, centered on Monday on the major central metropolis of Taichung, only basic mobile phone services worked, though key services, from ATMs and traffic signals, were not affected, and neither were landlines nor fixed internet services.
Air raid sirens rang out in Taichung and people cleared the streets from 2:30pm (0630GMT).
The government has widely flagged the drill, sending on Friday afternoon a text message alert to mobile phones across Taiwan in both Chinese and English and posting details on social media.
Northern Taiwan, including the capital Taipei, will see the same exercise on Thursday.
TAIWAN STRAIT DRILLS
Taiwan's government rejects Beijing's sovereignty claims, saying only the island's people can decide their future.
Earlier on Monday, Taiwan's military simulated repelling a Chinese air landing assault on the strategically vital Penghu Islands.
The 10-day Han Kuang exercise kicked off last week, rehearsing various scenarios should China, which views democratically governed Taiwan as its own territory, ever make good on threats to try and seize the island by force.
Reuters was given rare access to the exercise, observing ground troops loading tank ammunition and taking up firing positions in darkness before the drill began.
Troops from the First Theatre Command opened fire in the pre-dawn hours on a beach in Penghu, which sits in the Taiwan Strait, with M60A3 tanks, various artillery pieces and anti-aircraft guns.
The troops were combining to form what the military called a "multi-layered" defense against a simulated enemy attempting a rapid coastal landing.
Penghu, which sits closer to the coast of the main island of Taiwan than to China, is seen by Taiwanese strategists as a potential first target for Beijing, which could try and take the islands and use them as a base to attack Taiwan with missiles and drones.
Reservists from Penghu took part in the exercise, part of their 14-day training program as Taiwan's military works to better integrate reserve forces into its operational planning and make its preparations more realistic.
