BEIJING’s controversial artificial islands in the disputed South China Sea are now bristling with fortified gun towers, new satellite photographs reveal.

This is despite repeated assurances from Beijing that it would not militarise these outposts.

The Asia Maritime Transparency Initiative (AMTI) first highlighted mysterious hexagonal-shaped structures under construction at the Spratly Island’s Fiery Cross, Mischief and Subi Reefs in August.

A fresh batch of satellite photos taken in November show these are being completed as point-defence fortifications housing radar-guided anti-aircraft and antimissile guns.

This means all seven of China’s artificial islands in the South China Sea are now armed.

Several countries claim territorial rights to these reefs, and the rich fisheries, resource stocks and trade routes they sit astride.

When asked if the weapons meant the islands had been militarised, retired US Admiral Mike McDevitt said the answer was in the eye of the beholder. “(But) if you ask any serving or retiring military officer, these islands are already militarised.”

However, a recent ministry of defence press conference in Beijing sought to reassure the world that the island features were for peacetime use — “except for appropriate self-defence measures.”

AMTI, however, says the weapons means China is asserting itself as an unassailable, dominant military presence across the contested waters of the South China Sea.

“This is militarisation,” AMTI director Greg Poling is quoted by Reuters as saying. “The Chinese can argue that it’s only for defensive purposes, but if you are building giant anti-aircraft gun and CIWS emplacements, it means that you are prepping for a future conflict.”

SAND CASTLES

The AMTI report states these fortified structures appear to be an ‘evolution’ of gun towers already placed on smaller artificial islands such as Gaven, Hughes, Johnson and Cuarteron Reefs.

Some hold what appear to be anti-aircraft guns, the remainder house objects that are less clear “but are likely CIWS (close-in weapon systems) to protect against cruise missile strikes,” say the Center for Naval Analyses’ Admiral McDevitt and RAND defence analyst Cortez Cooper.

AMTI says the gun and probable CIWS emplacements prove Beijing is preparing for future conflict.

“It would make a lot of sense to make a system (that can) engage incoming, sea skimming missiles. It makes a lot of sense in terms of being able to defend the airfields, defend the radars,” Mr Cooper says on an AMTI podcast.

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Such heavily protected, permanent weapon systems would quickly be enhanced any rapid deployment to the Spratlys of mobile surface-to-air missile (SAM) platforms, such as the HQ-9 seen deployed to Woody Island in the Paracel Islands earlier this year.

And such a prospect may not be far off. A recent Fox News report revealed components for surface-to-air missile systems have been seen at the southeastern Chinese port of Jieyang, possibly destined for the South China Sea.

“I worry about people who think of these (island) features as mere speed bumps, as iddy-bitty little things,” Admiral McDevitt adds. “But when you compare what they looked like in 2011 versus what they look like now, these would be tough targets. They could suck up a lot of cruise missiles. They would not be something you could easily shrug off.”

UNIFORM FORTS

AMTI reports many of Beijing’s island defences appear to have been built to near identical, though segmented, designs.

The smallest islands have a central headquarters building, each with four ‘arms’ extending from the central structure. At the end of each arm is a hexagonal platform or tower. Larger islands appear to have chains of two hexagonal towers (with one gun and one CIWS each), often alongside a radar dome.

Some, such as those at Mischief and Subie Reef, are large and complex web of hexagonal fortified towers housing a variety of weapon systems.

All are positioned in a four-corner arrangement on their islands, providing interlocking 180-degree fields of fire to cover all approaches, AMTI says.

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“It gives every impression of being a land-based attempt to put close-in weapons systems that you would normally find on a naval ship on a concrete superstructure on these features to provide some sort of close in, last ditch ... rapid firing weapon system,” Admiral McDevitt says.

“Looking at those structures, I’ve been sitting here puzzling over the hexagonal shape of them and looking at how they’re put together, first of all it’s reminiscent of a crazy-quilt superstructure of a ship ... but it seems to me the way those hex patterns are you get some possibility of deflecting radar targeting in the warhead of a missile ... They may also be resistant to penetration or cruise missile damage because of the inherent strength of the structure.”

AMTI points out earlier photographs of the emplacements while under construction revealed additional adjoining hexagonal structures appear to have been buried.

STAGING GROUNDS

Many of China’s artificial islands now have long runways and armoured hangar facilities capable of housing dozens of combat aircraft. Most also have extensive harbour facilities.

This gives Beijing’s coast guard vessels and surveillance aircraft a reach deep into waters throughout South East Asia.

But this capability has an inherently sinister edge to it. It would require little effort on Beijing’s behalf to turn these into active, offensive military bases, AMTI says.

These would be more than capable of enforcing a threatened ‘Air Defence Interception Zone (ADIZ) where all aircraft must seek prior approval from Beijing to cross what are regarded as international waters. A similar ADIZ was unilaterally declared by China over the East China Sea in 2013.

“When you put in runways, you put in barracks, you put in fuel and ammunition bunkers ... literally, overnight you could militarise,” Admiral McDevitt says. “You wake up one morning and all of a sudden there are aircraft there, troops have been flown in, ships have arrived in harbour. China has the ability to overnight change the military nature of these (island) features.

“If you have 72 fighters down in the Spratly islands it means you can maintain combat air patrols indefinitely, you can enforce an ADIZ over the South China Sea.”