They look like simple fishing boats but are capable of swarming in huge numbers to help Beijing stake its territorial claims in the South China Sea

Chinese fishing boats started swarming the Scarborough Shoal in the South China Sea in mid May. Some had already been drifting around the picturesque reef in the Philippines exclusive economic zone for some time.

However, the Chinese boats were not regular fishing vessels, and they weren’t there to fish. They were there to counter a Philippine aid flotilla aiming to deliver supplies to fishers near the disputed shoal. In the end, the aid flotilla turned back before it reached the shoal.

The Chinese vessels were part of a maritime militia, a shadowy armada whose existence Beijing rarely acknowledges and that it has long used to help hold or take disputed territory it says it owns in the region.

The militia has a long history in the area. Its key role in seizing Scarborough Shoal in 2012 set off one of the most high-profile territorial disputes in the South China Sea.

The shoal is just one of a range of sites that have seen dangerous clashes between China and other competing claimant nations. The tensions have escalated to make the South China Sea a potential flashpoint in one of the most strategically and economically important waterways in the world.

What is the maritime militia?

The maritime militia has existed for decades but has become more professional, better equipped, and more militarised under the leadership of President Xi Jinping, who has overhauled China’s armed forces since taking power in 2012.

It is made up of two main forces. One is the professional fleet of at least 100 purpose-built boats which have the appearance of fishing vessels. The other fleet, known as the Spratly Backbone Fishing Vessels (SBFV), is a larger group of actual fishing boats that operate out of ports across Hainan and Guangdong, and have been drafted into China’s missions.

The professional fleet consists of stronger boats with better, often military-grade equipment. They’re usually visible on satellite tracking platforms swarming around disputed locations.

The SBFV is harder to spot, and usually have lower grade satellite transmitters or none at all. Some have had structural and technological upgrades.

Crews in both fleets are believed to be civilian fishers and sailors as well as ex-military personnel recruited through a Chinese government training program. The vessels tend to have a smaller crew of about five to six if engaging in militia activities as opposed to genuine trawling, according to South China Sea expert Greg Poling, director of the Asia Maritime Transparency Initiative (AMTI).

How are they funded?

Militia are primarily funded through various government subsidies, and some personnel receive full-time salaries from state-owned companies, according to the AMTI. The SBFV crews also receive lucrative government fuel subsidies for militia missions, an income that disincentivises them fishing.

"These [crews] could fish if they wanted to, and occasionally they do, but mostly they sit quietly and then raft together [at disputed locations],” says Ray Powell, director of SeaLight, a maritime transparency project at Stanford University. “It’s most economical to just sit there and not use the fuel.”

A 2021 investigative report by the AMTI said there was “no longer any question about whether the militia is organised, funded and directed by the government of China”. It said Beijing was legally responsible for the militia’s actions, which “violate several tenets of international law”. The Chinese government rarely acknowledges the militia’s activities, or that they are anything other than fishing boats operating in what they say are traditional Chinese waters.

Beijing defends its operations in places like the Scarborough Shoal as acts of “rights protections”, but rarely concedes that the militia is part of it. It acknowledges the existence of the militia, but is “cagey” about what boats are actually in it, says Powell.

Employment contracts and state media articles reveal explicit directions from officials regarding their “political responsibilities” to operate in particular areas, and support the military when required. Towns that develop professional militia fleets have received government accolades and even visits from Xi for their efforts.

How does it operate?

The militia operates across the region, including the Yellow Sea and in the exclusive economic zones of Indonesia, Vietnam and Malaysia, but right now observers are focusing on activity in the South China Sea, where the brinkmanship is escalating, especially with the Philippines.

The fleets conduct intrusive journeys through foreign exclusive economic zones, blockade disputed reefs and islands, and have repeatedly rammed or used water cannon on other vessels in dangerous manoeuvres, including against the US Navy. Militia boats will often raft together to create a risk of collision and impede access, or camp out at a reef for months, strengthening China’s physical presence in a region where that presence is key to controlling a site.

Statements from Chinese officials suggest the professional fleet is called on first for more aggressive operations.

“The professional fleet is a direct threat, but smaller. The [SBFV] fleet is larger but a nuisance. They just drop anchor,” says Poling. “Governments have to treat them in different ways. One is a military threat, and one as a pain in the neck, which is a law enforcement problem.”

What have other countries said about it?

World governments and bodies have repeatedly condemned China’s behaviour in the South China Sea, including operations involving the maritime militia.

The US, which is a treaty ally of the Philippines, has repeatedly accused the militia of violating international law “to enforce its expansive and unlawful maritime claims”.

The Philippines, which is the target of most recent militia activity, says it “will not be deterred from pursuing legitimate and lawful activities in our maritime zones”.

Poling says the Philippines is pushing back more than it used to.“On the Philippines side they don’t see any other option,” he said.

It hasn’t really responded to the regional resistance, Poling says, and is instead “pushing the Philippines and other neighbours to form anti-China coalitions”.

“China was willing to do crazy stuff and everyone backed down [in the past]. But now they’re not, and like a school bully China doesn’t know what to do now.”