‘A Warning Sign’: Chinese Ships Accused of Cutting Off Internet to a Taiwanese Island

A Taiwanese archipelago has been knocked offline following repeated damages to its undersea cables. Taiwan suspects Chinese vessels are responsible.
Internet outage in Taiwan’s Matsu islands has raised speculation of Chinese sabotage. Photo: Rutget van der Maar via Flickr

Spring is usually a busy time for Fu Cheng-wei, who owns a bed-and-breakfast on the Taiwanese archipelago of Matsu. At night, starting in April, miles of bioluminescent algae light up the shores in a phenomenon known as blue tears, drawing flocks of visitors to the islands.

But for the past month, Fu has been struggling to keep his business running. Websites wouldn’t load. Phone calls keep dropping. To handle bookings, Fu and his wife have been split across Taiwan’s mainland and the archipelago, communicating through text messages that could take up to hours to load. 


Fu is among Matsu Islands’ 14,000 residents whose lives have been thrown into disarray since February, when alleged Chinese ships severed—within a week—the two submarine internet cables that keep the islands connected to the rest of the world. 

“We aren’t the only ones affected,” said Fu, whose boutique hotel, Mu Light, is one of dozens that dot the largest island of Nangan. “70 to 80 percent of the island’s economy is supported by tourism, including motorcycle rental, hotels, and tours. People are concerned if tourists will still come.” 

Taiwanese authorities have blamed a Chinese freight ship and a Chinese fishing vessel for the damage but suspected no foul play. Chunghwa Telecom, the telecommunications provider, also stressed that there’s no evidence the cables were tampered with intentionally. 

But the relatively high number of breakages in the islands’ two cables—27 times in the past five years—has raised eyebrows and prompted questions on whether they were mere accidents. While undersea cable experts are skeptical of such claims, some defense analysts have speculated that they’re part of China’s wider campaign of harassment against the self-ruled democracy, which it claims as part of its territory. 

“China has a track record of relying on unconventional means to make territorial claims or gain strategic advantages,” Christian Bueger, a maritime security expert and a professor of international relations at the University of Copenhagen, told VICE World News. “Given this track record, it’s likely that China considers exploiting the vulnerabilities of subsea cables for strategic and signalling purposes.”


China’s foreign ministry did not immediately respond to a request for comment.

Matsu sits less than 10 km from China at its closest point and served as the Nationalist Party’s first line of naval defense against the Chinese Communist Party when it retreated to Taiwan during the civil war and set up its own government. Today, Matsu’s military relics and natural landscape draw about 300,000 visitors to the islands every year, who sip coffee by the sea and explore subterranean tunnels.

But the tranquil hideaway could now be a site of geopolitical contest. 

To put pressure on Taiwan, China has deployed gray zone tactics short of direct acts of aggression. It often sends warplanes into Taiwan’s air defense zone and, in a military exercise last year following U.S. House Speaker Nancy Pelosi’s visit to Taiwan, dropped bombs near its coast.

Taiwan’s military experts have warned in the past that the frequent incursions of Chinese sand dredgers, which have sent Taiwanese coastguards scrambling, are one such tactic. “Sometimes I’d look up to see twenty or thirty sand dredgers along the horizon,” Fu, the bed and breakfast owner, said. 

Dredgers accounted for 10 of the 27 ruptures in Matsu’s cables, which are the width of a garden hose and lie on the surface of the seabed. Local media suggested the sand extraction could also further expose them, increasing the risk of damage from bottom trawling and dragging anchors, which account for the rest of the breakages. 


Bueger’s assessment echoed that of local officials, who said they cannot rule out any possibility and considered the latest disruption “a warning sign” for the entire country. “If an internet outage could happen for Matsu, the same thing could happen for Taiwan,” said Wen Lii, head of the local office of Taiwan’s ruling Democratic Progressive Party. “What would we do if Taiwan’s 14 international sea cables were damaged?”

The consequences would be catastrophic, as undersea cables carry more than 95 percent of international voice and data transfer, from emails and video calls, to e-commerce transactions and scientific research, to government and military communications. 

This was the case for Tonga last year, when a volcanic eruption severed crucial cables and knocked the Pacific nation offline for weeks. As Russia’s invasion of Ukraine demonstrated, a widespread internet outage would be even more devastating during a conflict, sowing chaos and cutting off communications.

For Taiwan, the prolonged internet outage on the outlying islands has highlighted the fragility of its internet infrastructure, renewing the urgency to boost its capacity. The Taiwanese government has already announced plans to pour $17 million into bolstering its mobile infrastructure last year, amid concerns its internet could be targeted in the event of a Chinese invasion. This week, the legislature also passed a new motion to improve local operators’ capability to maintain the undersea facilities, while local officials, such as Lii, proposed exploring other technology, such as satellites. 


According to Chunghwa Telecom, the cables cannot be repaired until a cable-layer arrives in late April with a cost of up to $1.3 million. “With the number of cables in the world only increasing every year and a shortage of vessels and crew, especially fiber jointers, the lead-time for a repair can be months,” said Julian Rawle, an undersea cable specialist who runs his own consultancy.

A new cable—this time buried 1.5 meters under the seabed—is also in the pipelines and expected to be completed by September 2025. But in the meantime, islanders can only rely on the backup microwave internet with limited bandwidth. “They keep saying they are actively finding solutions, but we see very little actual improvement on the ground,” Fu said. 

Across the strait, China also appears to be expanding its control over the submarine cable system. Chinese state-owned telecoms are acquiring stakes in newly deployed cables around the world. The Financial Times reported this week that Chinese authorities are hampering efforts to lay cables in its territorial waters, forcing companies to design routes that bypass the South China Sea. 

“More governments are paying attention to how submarine cables can be possible vectors of espionage, capacity-building, economic dependence, and influence-projection,” Justin Sherman, CEO of Global Cyber Strategies, a Washington-based research and advisory firm, told VICE World News. Beijing’s growing hold over the cables could raise the risks of them being used for geopolitical purposes, he added. 


“The Chinese government is also well-attuned to how the internet, including physical internet infrastructure, can be weaponized for information control,” Sherman said.

Despite the concern, experts on undersea cables say threats of sabotage have been overblown. “It’s a little unusual, but hardly proof of malicious activity,” said Tim Stronge, vice president of research at the telecommunications market research company, TeleGeography. 

Fishing and ship anchors account for 70 percent of around 200 cable faults worldwide each year. The shallow waters of the Taiwan Strait and Matsu’s proximity to China, where a large and not well-regulated fishing fleet operates offshores, are factors that could contribute to the damage, Stronge added. 

“The industry has its eye on the possibility of a low likelihood, high impact event of a state actor intentionally cutting cables,” Stronge said. “However, they largely agree that there is much more urgent work to protect against the very common breaks caused by accidents by fishing vessels and larger ships.” 

Australia, for instance, deploys air and sea patrols to guard cable protection zones, where potentially damaging activities are restricted. Automatic identification systems are also used in many parts of the world to monitor vessel movements around cables and warn ships’ captains if they are too close, according to Rawle, the submarine cable specialist.


John Wrottesley of the International Cable Protection Committee said Taiwan’s case highlights the need for diversity of routing and redundancy. “Smaller island nations often rely on fewer connections, and so if they have two cables but they suffer faults at the same time, this can cause greater disruption or outages.” 

But Bueger, the maritime security expert, argued that motivation could be difficult to discern. 

“It can often be unclear whether these damages are intentional or not. While some of them are clearly the outcome of accidents, others are clearly at least acts of negligence or taking the deliberate risk of damaging cables, since cable locations are marked on maps,” Bueger said. 

“This implies that if a state would have the intention to damage a cable, it could do so in a way it cannot be appropriated,” he added.

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