For nearly four years, Houthi forces have victimized both coalition warships and commercial vessels in the Red Sea. These strikes, which date back to Oct. 2015, have caused significant worries in the international shipping community.

Data from these naval attacks was gathered from Arabic and English-language media by FDD’s Long War Journal in an attempt to present a more complete picture of Houthi capabilities – on land, in the air, and at sea. In many instances, the Houthis themselves did not self-report the attacks.

Given the rate of piracy in the area, only attacks explicitly blamed on the Houthis were added to the database.

It should be noted that an exception was made for the April 2018 incident in which Saudi officials accused the Houthis of taking 19 commercial vessels hostage in Hodeidah.

However, owners of the ships, and maritime experts, disputed this and found that the ships were not actually being held by the Houthis.

Much like the other aspects of the Houthi military arsenal, Iran has been widely suspected in aiding the Houthis maritime capabilities. Officials have warned that the insurgents’ suicide drone boats are likely manufactured with the aid of Iran.

Additionally, the use of the Chinese-made C-802 anti-ship missile, which has been reproduced by Iran, indicates that these were likely supplied by the Islamic Republic to the Houthi rebels.

These missiles have been found elsewhere within Iran’s so-called ‘axis of resistance.’ For instance, C-802 missiles were also used in two Hezbollah naval attacks during the 2006 Lebanon War. At the time, military experts and international officials found that Iran supplied Hezbollah with these weapons.

Houthi attacks in the Red Sea

FDD’s Long War Journal has documented 40 Houthi naval attacks. These strikes began rather unsophisticated, with some being the result of rocket-propelled grenades (RPG’s), and have advanced to more complex means, utilizing sophisticated remote-controlled vessels as the war has progressed.

These numbers are generated from each individual report of a naval attack and does not represent the total number of individual anti-ship missiles or suicide drone boats used.

Fifteen maritime strikes were claimed in the Bab al Mandeb Strait, nine came off the coast of Hodeidah (which saw fierce fighting last fall), and seven off of the coast of Mocha (which was captured by the coalition in Feb. 2017).

Four more were recorded off the coast of Jizan, Saudi Arabia; 2 off the coast of Midi, Yemen; and one each off the coasts of As Saleef, Al Khokha, and the Abs District of Hajjah Governorate.

In 22 of these instances, anti-ship missiles, which were reported to have been Chinese C-802 anti-ship cruise missiles (or the Iranian-copied Noor missile), were used. Footage released by the Houthis appear to confirm the use of these anti-ship missiles.

In another nine instances, remote-controlled suicide boats were utilized. The rest were either the result of unsophisticated attacks with small arms or were not specified in the reporting.

The first reported attack utilizing suicide drone boats was the Jan. 2017 attack on a Saudi warship off the coast of Hodeidah. Two members of the ships crew were killed in the explosions.

In June 2018, the Saudi-led coalition showcased captured Houthi weapons and material in Abu Dhabi. Included in this exhibition was the first look at a Houthi ‘suicide drone boat.” This boat appeared to just be a modified private speed boat fitted with explosives.

However, in Sept. 2018, the Saudi-coalition released more information on how Houthi remote-controlled suicide boats are manufactured and used.

From the photos released by the Saudis, the design of these remote-controlled boats appears to have shifted to a more smaller frame with more technical components.

In July of this year, more photos of this variant of drones, referred to as the “Blow Fish” by the coalition, were released to the public.

US officials have cautioned that this design and the successful nature of these drones indicate outside support in their manufacturing. It is likely that Iran has aided the Houthis in this regard, as well.

Warships belonging to the Saudi-led coalition, as well as other warships, have been routinely targeted by the Houthis.

Warships from Saudi Arabia and the UAE were targeted the most with 21 instances.

The US warship, the USS Mason, was fired upon three times with anti-ship missiles by Houthi militants in Oct. 2016. In each case, the Mason’s defenses were able to counter the anti-ship missiles.

Following these attacks, the US Navy launched a cruise missile strike on a Houthi radar position on the Red Sea coast – resulting in the first time US forces targeted the Houthis.

On May 10, 2018, Turkish ship Ince Inebolu was targeted by the Houthis near the port town of As Saleef. The ship was reportedly carrying food aid to Yemen when it was reportedly hit by a missile off the coast. This is not the first time an aid ship was attacked by the Houthis.

In Oct. 2016, the Emirati-flagged aid ship, the Swift, was hit by a Houthi missile in the Bab al Mandeb Strait. And while not claimed by the Houthis, an attack on a World Food Programme in the Strait in June 2018 has been blamed on the insurgent group.

Not all Houthi claims of naval operations on foreign warships have been legitimate. For instance, in Oct. 2015, the insurgent group said its men struck an Egyptian warship, the Al Mahrousa, in the Red Sea.

But maritime experts later said that the Al Mahrousa is a centuries-old yacht and not a ship within the Egyptian naval fleet.

Tapering off

Since Jan. 2018, Houthi naval attacks have dropped off significantly. This slow-down and the now sporadic nature of naval attack claims appears to be directly linked to the loss of territory to the Saudi-coalition.

That said, on July 8 of this year, a commercial vessel was targeted by a suicide drone boat. The Saudi-coalition stated that its forces managed to intercept and destroy the remote-controlled vessel, however.

Merchant or civilian vessels have also been explicitly targeted at least nine times. In five of these cases, suicide drone boats were used, indicating that the Houthis have utilized this tactic indiscriminately.

While not on the map, it is also important to note that Saudi officials stated in Nov. 2018, that over 80 Houthi-placed naval mines have been disarmed in the Red Sea since March 2015. In Jan. 2019, another 10 Houthi-placed mines in the Red Sea were reportedly disarmed by Yemeni forces.

It is unclear if more have been disarmed since then. The presence of non-disarmed naval mines in the Red Sea obviously constitutes a major worry for international shipping, highlighting one of the Houthi movement’s most potent threats.

Despite being a lesser focus of the Houthi military apparatus, and underreported in the media, naval attacks conducted by the insurgent movement constitute a real threat to shipping in the southern Red Sea.

Third in a Three-Part Series. Part One, on the Houthi missile program can be viewed here. Part Two, on Houthi drone strikes, can be viewed here.

Caleb Weiss is a contributor to FDD's Long War Journal.

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